I've had motorcycle wheels trued and then powder-coated in the past.
I also know of a place in Melton Mowbray called Alloy Wheel Repair who do a very good job.
WillB gets sets refurbished all the time (edit: I have no idea where but he lives just near the M25 in Berks I believe).
And there is a company that has just recently set up shop in Nottingham called Total Wheel Works. By coincidence I just joined a queue of traffic behind their pick-up truck a couple of evenings ago.
I recently was given a complete set of SE wheels which are in need of some TLC.
Total Wheel Works quoted me £160 to completely sort them out. This includes stripping, trueing and respraying. They even offer a 24 hour service. So I'm taking them in on Friday!
I'm sure you should be able to find something a bit more local to you though. WillB may even have some for sale.