I've painted two bumpers so far (one being my own) and I've decided to offer a rear bumper color-matching service to members in the Bay Area. It takes around 4 hours to do and I can take it off and install it back on for you, but you have to come to me.
I figure $100 should cover the price of paint, materials and time on my part.
Let me know what you guys think!
Pictures of already finished grilles:
Update from this weekend, colormatched a white and radiant red bumper: