Deteriorating door handle -- solved -- see update below

Is this about a foam sleeve or some other material? Expanded foam is very difficult to make and withstand UV. I'd suggest to think outside the box on this and defer to a different material. Crocodile leather or shrink tube come to mind, lol.

I'm also interested in that Krylon paint Barney recommends. Fortunately, I don't have a lot of plastic on my TT.