Rep Power: 762

I have some 16" allow rims on my car. I don't have a problem with them at all, but they kinda got rusty. Now I'm thinking on having them painted. I wouldn't mind chaging the colour to something like gun-metal . The problem is that I have no idea on where to start looking. I would much rather have a store do them professionaly, but I don't know how much it would cost. I read a bit and they seem to need to be powder coated and sanded down. Any recommendations of places on getting it done?