I couldn’t find a door that I liked. RV doors are pretty flimsy and I also don’t like the rounded top corners on many of them. I liked the construction of the doors on the ambulances I used to haul so, I constructed mine similar to them. It’s basically two aluminum pans glued to each side of a steel frame.
I built the frame and had the tin shop bend the aluminum to those specs. I should have game them the specs and built my frame to fit inside. I could have gotten a much tighter fit. I had to shim thing to get it tight enough. Then I had to redo the door frame because it was just a tad too tight.
I have a very nice sliding screen door from Plisse screens. They custom make it to your dimensions.