I have used a guy in Essex http://www.powdercoatingessex.co.uk/
for a few motorcycle related coating jobs and was very happy with the finish and colour match.. He also said he is doing more and more cycle frames so atleast if you take a frame to him it wont be the first he has done..
I think I will be taking my newly acquired frame to him later next week and see what the out come is. I have no idea if the frame is worth anything so dont have any problem if it turns out a bit of a lemon
see the thread http://www.retrobike.co.uk/forum/viewtopic.php?t=117582
for a explanation..