There is an extensive list of RV suppliers and parts on the forum. It's located in the Repairs and Maintenance section and is the first thread there.
http://www.keystoneforums.com/forums...ad.php?t=12986
You might find a salvage yard in your area, but finding the part you need in a salvage yard is going to be much more difficult than finding parts for a car or truck. The "network connection" allows auto salvage yards to work together to find parts. I don't know of any "networking" that is being done in the RV salvage business.
There are several threads on the forum that would give you some ideas on how to approach a repair without replacing the door. Do a search for "Front compartment door" or similar to find them. Good Luck