Just a thought but if you applied protective film yourself, might be less expensive. The link below sells this stuff and I would think you could install by slightly overlapping more narrow pieces (not the 8' width of your cap). Doubt the overlap would be unsightly. Take a look... never used this company and there are probably others:
https://www.rvinyl.com/paint-protection.html
Lots of motorcycle trike builders use this type stuff on fenders that catch a lot of small stones and would otherwise get nicked up.