I have a 2008 Jackson horse trailer that the “nose” window 37" X 15" blew out. It is convex. I called Jackson and they don’t make that replacement window. This window was set in a welded frame so I can’t just put a new piece of glass in it.
Could you go to a custom glass shop?? They have fixed some doozies for me that I didn’t think possible.
That’s what I am going to try next.
Our trailer shops here make all those themselves as needed for each trailer.
Surprised yours won’t, maybe is a very small, basic repair place in a dealers store.
Maybe try other repair shops?
A shop that does vintage car glass might be an option.
One hot rod we have needed a custom back glass. They had to make a custom jig to create the glass and frame. Seems logical they could do similar for a trailer window.