There is a frim in Milton keynes i think it is that everyone raves about on the rsoc. Only knew this as Im wanting to get mine done in the near future as the clearcote is starting to look aged
http://www.pristinealloywheels.co.uk/about-us.html
Aso someone mentioned these but no idea.
http://www.lepsons.com/
I suppose any wheel refurber can do it to a degree but i think id prefer someone who's got a reputation for these wheels to do mine. Some people spray them blak then diamond cut but im sure its a very very dark grey. Thats the difference between a good job and a great job for me. Knowing your onions and getting it perfect