I think the windows you are referring to are commonly called wing windows. I have heard the term panorama windows referring to the small long windows above and below the primary side widows. But you are talking about the curved front side windows.
I suspect eliminating a wing (paroramic?) window may be a project you may have to fabricate. I also suspect that they are originally made as a solid blank with the window hole cut out in the fabrication process. I doubt they are manufactured blank for sale, but the only way to tell is call mothership. To replace the whole panel would, again guessing cost more than just the wing window.
If the window is not a compound curve it should be able to replaced with one panel with a little skill. If it is a compound curve you will need something like an English wheel, and more skill), to do it in one piece. Get a piece of poster board and see if you can bend it to cover the curve of your original window space.
You may be able to use sheet UV resistant Lexan (polycarbonate) to fashion a replacement. Lexan is more workable, and UV resistant, non yellowing than plexiglass.
Sail on silver girl. Sail on by. Your time has come to shine.