Try these guys, I know they're off your beaten track but I used them 2 years ago and wouls reccomend them
J.R. Finishright
Mulberry Trading Estate, Foundry Lane, Horsham, West Sussex, RH13 5PX
Check them out in the yellow pages; they have their own web-site too. I took mine to their shop near Pease Pottage (off the M23 at the Crawley Junction)
Was well satisfied. They stripped the old stuff from my battered frame and stuff and re-powdered it nicely.
Hope this helps