Hello
Good find!
I have refinished many pellet stoves.
I vacuum out the ash and then wire wheel it. For the tight rough spots a small grinder such as the Home Depot Husky brand pneumatic right angle die grinder works well
Husky Angle Die Grinder Kit is designed to provide more power, less noise and longer life. Features rubberized handle over mold for comfort.
www.homedepot.com
For the easy access areas I like the small 4.5” harbor freight electric angle grinder with a flap pad.
Amazing deals on this 4-1/2In 5Amp Angle Grinder at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
After that, I clean up the surface dust and oils with Acetone so the paint sticks better.
Acquire the Klean-Strip 1 qt. Acetone QAC18, liquid acetone is an effective cleanup solvent after the completion of a fiberglass project at The Home Depot
www.homedepot.com
The spray paint I use for the fire box is VHT flat black 2,000 Deg very high temperature header paint at your local auto supply.
The outside paint, I use the Stove Bright Satin Black 1,400 Deg paint
That’s all

Media blasting helps too.
I have used Tractor Supplies Black Diamond media but I prefer white aluminum oxide
White aluminum oxide (Uniblanc. Condition is New. TM ) is at least99.5% ultra-pure. It sparkles when light hits it and has been used for decorative purposes. Very friable material. Most extensive range of grit sizes.
www.ebay.com
Here is an old Quadrafire Classic Bay I did a little refurbishment with pics.
Hello This Quadrafire CB1200 has see alot of use in a basement that may have had some dampness. Dampness is the Pellet stove's # 1 adversary! Even though it works fine, looks like time for a little touch up? I brought out the Big Gun by using a 40 lb Abrasion blaster connected to a 210 PSI...
www.hearth.com
Hope this info helps.