I use cheap acrylics from the local craft and sewing supply store. Usually $1 - $1.50 for 2 Fluid Oz (59ml), and they have a pretty wide range of colors; including a metallic range and some effects (cracking, thick gloss, etc) paint options. Not sure how it stacks up to small pots of paint, which can be matched, but they do the trick for me. If you have an art supply store around, you can probably also pick up student acrylics by the liter. Just depends on how much you need/want.