The door is a pain to find! One from a truck camper might work. I ended up building one from a household plywood interior door cut down to size , I then laminated white Formica inside and out. Installed the original aluminum trim and replace the latch with a Fastec lock and
sold the old one on ebay for $120 (Bargmann L400's are rare and worth a far bit).
As far as the
fridge, if it works on gas then you should be able to get it working on AC and DC fairly easily. If worst case find a dead one and grab what you need. There was a great trouleshooting page but the link is dead
I will see if I can find the info. There are a lot of manuals for dometic in the document center. The best bet for replacing these small fridges are ones from a tent trailer. Find someone gutting one due to moldy canvas and you can probably get one for less that $50.