What Gene from NE said.
I've had several of them, and to me, they're just short of a nightmare. They wore through on many of the sharp places or corners in less than a year, unless I reinforced or padded that area. Then the pad falls out, and there's your hole. That cover will be heavy. If you can figure out a way to "shed" your unit, that would be best.
I rented an enclosed storage and have never looked back, even though it costs a pretty penny.
Anyway, to sort of answer your question based on my experience, I bought a couple custom made, and one universal. The universal was pretty floppy, and seemed "taller", so maybe they would fit yours. I think the universal stated maximum height for the RV. I bought one that was about 6" shorter than recommended, and like I said, it was floppy.