We priced out the direct replacement white doors for our Morgan at Atlantic Coast Trailer in Kernersville, NC. About $800 installed.
There's also a trailer supply place in Conyers, GA, that said we could buy the doors for about $500. But I wouldn't even want to begin to try and hang those things myself.
Lastly I think you can get a decent price directly at a Morgan facility. They quoted us a day downtime with about a couple of weeks scheduling advance time.
Hope that helps Butch.
The Gibster