I think this is strictly a matter of preference.
For starters, the home would likely be more comfortable if you can do something about the heat loss from the unfinished basement through the floor to the first floor. Is it a full basement with insulated concrete slab, a crawl space with earth floor, or somewhere in between? If a full dry but unfinished basement, you could consider insulating the basement ceiling, hanging an insulated ceiling, or putting thick underlayment and carpeting in the area on the first floor, any of which would mitigate the heat loss problem.
I had the Fireview and upgraded to the PH. (Woodstock might well let you trade in for near full value, which would not make the PH too much more expensive). The difference in heat output is remarkable...in keeping with the difference in rating of 55,000 BTU vs 80,000, using very little if any more wood in the process. So much more heat comes through the large window, I'm sure because of the angled fireback as well as the very large window). With a small fan blowing colder air from the rear of the home, I'm pretty sure the PH would add enough heat to make the back much more comfortable. Nothing but insulation will stop that floor from being cold, but the stove will put out enough heat to heat the air, Also, keep in mind that the PH is an excellent stovetop cooker. One can keep things warm on the soapstone top, or cook slowly on it. Raise the soapstone and one has a full cast iron cooktop, with three different temperature "elements" or areas. I do ALL my cooking on it from shoulder season to shoulder season, except for minimal microwave usage. I even rig an oven on top and do much baking on top.
I understand the desire for a cookstove. I'd love one, mostly for sentimental reasons as my grandmother had a beautiful massive Findley in the country kitchen, but unless you are putting the stove in a kitchen, or adjacent to a kitchen and between the kitchen and dining room, be certain it is in a convenient spot where you will actually use it as a cookstove. Unless you have handy counter space etc, and lots of clearance for the stove, the added need of obtaining and carrying extra firewood for a second stove could be an unnecessary nuisance. Also, unless the enclosed rear porch is well insulated to the outdoors and has a large opening to the kitchen that you can keep open all the time, you might not get much heat out of the porch into the back area of the home. May lose most of it to the outdoors. May even get more cold air into the home opening the door to the rear porch if it is uninsulated and you do not use it regularly in the winter now. Plus you have the cost of installing the stove. And perhaps the cost of a building permit, and perhaps even higher insurance premiums with a second wood heating appliance. And you lose a lot of otherwise useful space in the rear porch. And the necessary hearth for under the new cookstove, as well as the question of whether the porch is built to take the weight off the cookstove, or whether you'd need to reinforce the floor underneath. And is the cookstove efficient or an older/less efficient stove?
The PH slips right onto the hearth where the Fireview was and will connect to the same stovepipe. If you go from rear vent Fireview to top vent PH you do not need to make ANY adjustments to install, and the stove sits a mere 7 inches from the wall, and comes less far into the room than the fireview. A significantly larger stove that produces masses more heat when required, but can easily be burned at low heat output, the PH actually takes less space in the room, sits on the same hearth pad, and provides a far superior viewing ambiance.
I'm pretty sure that when all finances are considered (cost, install cost, hearthpad, time) that the PH upgrade will be less expensive and more satisfactory and enhance your life more, compared to a cabin cookstove. Also think it will continue saving more over its very long life, as you both use much less wood than you would with a second stove, and do less work supplying the wood, and use the PH more for cooking than you would a second stove, continuously saving on gas/electricity vs. present cooking in the kitchen.
I have lots of cast iron cookware, but I went and bought some inexpensive deep blue enameled cookware at Target last year and used the pots and frying pan all season on the PH. Have four, from quite small to a very large pot (maybe 8 quart). They look great on the stove which sits proudly center front in the living room. Paid $100 for all four. They are not heavyweight, but cook just fine on the stove, with no issue of burning despite the fact that they are light.
Long reply, but I hope helpful. Basically, carefully think through all the long term ramifications of your choice, as you'll be living with the stove/stoves for a very long time. Keep in mind, for instance (I have no idea of your age/family situation) that as children grow they demand more time, and keeping two stoves going takes time. As we age, gathering firewood and loading stoves becomes gradually more of a chore. If we suffer a knee or back injury or arm injury, at any time, an extra stove to load is a big hassle and will NOT at such a time be used for cooking.....A PH will last you a lifetime with minimal if any need for rebuild, while the story may be quite different with a used cookstove....Basically, a lot to consider.
The more I think of it, the more I'd lean strongly toward recommending a PH. It's what I would do (did do) in my home. Have had it for two years, after over 6 with a Fireview. Loved my Fireview, but absolutely no regrets.
I think you'd find you'd use the PH a lot more often than the cookstove for cooking, as you'd be heating with it all the time, instead of only on those colder days. No extra wood needed for the cooking. And if you did use it as I do, you'd save enough on power now used for cooking to gradually reimburse you for the added cost of the PH> Plus you'd be getting a beautiful stove with a far superior viewing window compared to the lovely fireview, a stove that will heat your home more quickly and in mild weather uses very little wood to quickly take the chill off a room. A quite small fire once a day does the trick because of the greater amount of heat quickly put out through the window, and the extra mass retaining more heat to slowly radiate. Also, two good loads a day is all you need with the PH, compared to 2 1/2 to 3 with the Fireview when you are heating a larger home. It's surprising how much more convenient and less work/time this involves. Lastly, if you like stews or soups. you can start one the evening before, and let it cook slowly till the following evening, and have it ready to eat when you come home from work, if all adults are out of the home for work each day. nice to come home to a warm dinner.
