Have you tried to contact your RV's dealer? As far as I know, some of them - Jayco at least - offers the slide topper awning as an option. That will put it under their warranty if installed at factory.
I've been full timing for over four years in an Arctic Fox 27 – 5L fifth wheel that has a bedroom slide and a living room slide. I see a lot of folks that have slide awnings but I've never been convinced they would do enough for me to justify the cost, the NOISY flapping in the breeze, I was camped next to somebody once and their flapping slide awnings just about drove me crazy. The chance of a strong wind getting under them and tearing them up, in the winter I'm mostly in the desert areas and the winds can come up out of nowhere. And just another thing to break or complicate my life.
I'm sure they keep stuff off the top of your slide but I guess I've never been in a place where things get on my slide because it's never been a problem for me, maybe I'm just lucky
I have just bought Lippert RV Solera Awning Black Slider. It has a host of features that make it one of the best. I mean, there isn’t much to complain about with this particular RV slide topper. But if you do intend on buying it, get ready to spend a small fortune. This model is easily one of the more expensive ones on this entire list.