I have found three used wood burning inserts to buy locally which all fit my opening. A Buck Model 91, Buck Model 74, and Hitzer 983. All stoves are in great condition and less than three years old. For the safety of my family I plan on installing a metal liner inside the clay liner. Not a big fan of a catalytic stove, which the 91 is I understand. Wood will not be the primary source of heat for 2,000 sq ft. home, I'm just trying to give the Geothermal system a break when we reach the teens temperature wise. I have plenty of seasoned Ash to burn thanks to EAB. Please share your thoughts. Thanks!