Here is a good thread with references to follow for a fridge build. I'll see if I can find a fridge build a guy did, very nice top loader in an older yacht. You can order all the parts, I think the cost will be about like buying some, the advantage is the custom fit, size and style, 12/24 or 120 volt. Never looked at propane. Ebay has a TEC unit for sale, $135 I think it was. Will watch your progress.
http://www.cruisersforum.com/forums/f115/aerogel-spaceloft-insulation-for-fridge-freezer-58888.html
Enjoy!
http://www.cruisersforum.com/forums/f115/aerogel-spaceloft-insulation-for-fridge-freezer-58888.html
Enjoy!