Everbrite coatings have been recommended on Pinside in the past: https://www.everbritecoatings.com/
I bought some Everbrite to level some playfield inserts, but haven't tried it yet.
Their ProtectaClear looks like it might be more of a wear coating.
https://shop.everbritecoatings.com/index.php?main_page=index&cPath=7
I think they use it on things like brass railings at casinos, so the stuff must be pretty tough.