Take a look on ebay under RV parts - "Baggage Doors". I believe that those are called "Faux Corners", I saw them last week.
Correction... Make that "Mock Corners" heres' a link, there are about 4-6 listings. http://www.ebay.com/itm/RV-Motorhome...item3cc4b714c9
I can get those corners for you. Replacement corners come in Polar White cost 3.10 each called mock radius corner. I would have to order them it would take a couple of days. Please email me at Fiberglass Travel Trailers RV
Chuck