hi we have an older fisher wood stove in our hunting camp i think its a papa bear or similar, has 8 inch single wall pipe. runs strait up thru roof, so its a top vent pipe not side . my problem is the collar on the stove itself where pipe attaches to at the stove has deteriorated with not much left to attach new pipe to. is it possible to weld a new 8 inch collar ring to the stove? or is there some type of after market part the can be bolted or welded on to the stove? frustrating as the stove works good any ideas ??? thanks