I've just refurbished my wheels. I was originally going to just send them for powder coating but decided to spray paint them myself because I wanted them black on the inside and silver on the outside for the original look.
First step was to get them blasted and phosphate dipped, this would get the old paint and rust off and put a protective coating on while I knocked out a few rings in the rims and filled some imperfections. This was done at in Tamworth and was £40 for 5 wheels.
The wheels were quite corroded in places, particularly inside the wheel where inner tubes had held moisture against the wheel. The outside where the rim is rivetted to the centre was also corroded and the blasting didn't get it all out so I ground it out with a small carbide burr on a Dremel.
The small imperfections in the visible areas were filled with stopping filler then I etch primed the wheels before painting and lacquering them.
Total cost was probably £120. I could have just had them powder coated in a single colour for not much more but I wasn't sure I'd be happy with the result as it can look a bit artificial. Overall I'm happy with the result, the don't look brand new but they're very presentable and with the chrome cap on, they should look nice on the car.
I'll post some pictures later when I can get on a computer, too difficult to do on the phone.