Your local crafts store will likely carry a line of acrylic paints in about a zillion colors (and you can mix to achieve shades not available right out of the bottle). The brand I happen to use is FolkArt. They give a perfectly flat finish, jis' lak' cuckoo brown. For a gloss, there'll also be an acrylic varnish you can mix in or apply on top. All water-cleanup, all water-thinnable (but waterproof once dry). That's where I'd look.