I am sure there are lots of options, but fingernail polish was the first thing that came to my mind. It is basically acrylic based paints if I remember correctly. But they have lots of clear coat options with varying levels of shine.
I don't have any specific recommendations but I do know that they make water based, brush on gloss, I've used some in the past when painting Star Wars minis. Just do a search on Amazon and you're bound to come up with results, or, if you have a decent hobby shop near you, go there and ask one of the workers.