i had the rims on both sets of my Porsches color matched by Keystone Automotive in williamsburg
what they do is totally make sure the wheel is traight and true then use high quality paint mixed to match then use a clear powdercoat over it and give it a lifetime warranty
now if you just wanted a standard color they can due regular powdercoating as well

here are some shots of the rims



here is a shot of one of the rims after an accident, it looked much better before this



they also restored the rims on my 78 TA and they look amazing, i will have to get some pics of that soon
what i like is the lifetime warranty, had some rock chips on one rim and he is going to fix it for free
pm me if you need contact into
good luck