Bob, I moved this to the Problem Solving forum out of Modifications since you need one rather than have modified one. Hopefully you'll get some replies. Is it possible to get some measurements? It's possible a door off some other trailer... maybe even a fiberglass sticky would get you by for a while.
Ten Forward - 2014 Escape 5.0 TA
Double Yolk - 1988 16' Scamp Deluxe