I have for sale a used Kozy heat wood burning unit. These are originally designed to be installed in a full masonry chimney built specifically for them. If you are knowledgeable about clearance to combustibles, you could buy some appropriate chimney and put this in a shop/ barn and it would be better and more heavy duty than the typical 55 gallon drum type wood burner.
I have a skid loader on site to load, open to offers/ trades. Please email me through Craigslist email link and include your name and phone number.