I removed my gas cap cover from my car and took it into Canadians Tire looking for a touch up paint that was the right color, but unfortunately, there was no exact match for my car.
I managed to find nail polish at the dollar store that was an exact match.
The only problem I had with it was after a few years the nail polish faded and looked dull.
A proper clear coat on top of the nail polish may have prevented the fading?
They also sell clear nail polish, but I don't know if it's as good as proper clear coat?