>>6496994 Honestly, I haven't overcoated my models with anything other than maybe sometimes clear flat enamel, picking out little details with gloss on occasion. I try to polish my canopies and other clear surfaces using a plastic polisher which you can find at auto supply or as a CD scratch removal paste. Toothpaste doesn't have consistent enough grains to get the job done and can be too coarse. 3M plastic polish is pretty good stuff and might give you the best deal for your money. Meguire's (car products) works. I still want to try getting a showroom floor finish one of these days but I don't have a kit to do it on at the moment.
Anyway, pic is the stuff I have on hand.
I think you can probably get a UV resistant acrylic matte. I'll have to check at some point though.
I've never used Krylon UV resist stuff, much less UV resist spray, so I have no feedback on that except I might try it if I ever find some.