Is here some sort of spray / paint protector i can use to protect plastics that i paint? ...
Answers: walmart sells a paind call "fusion" in spray can, that can be sprayed on plastic. it mostly comes in colors, but clears may be available. Another product, that may work, is Minwax PolyCrylic. it is a waterbase clear drying product available within satin, semi-gloss and gloss sheens, surrounded by both cans, and spray.