Alfine specialists...in the midlands

[Adrian@]

Advice please...on my wife's Opus Sketch, she is running a retro fitted Alfine hub with a CT-S510 tensioner which is rotating out and the chain becomes loose (this does not have a integral non-rotating element to the tensioner). So, I purchase through the guy who did the conversion a CT-500 which does now need a non-rotating washer set, that TBH, (I might be wrong) but they do not have a selection of non-rotating washers and do not appear to be able to envisage the correct ones to buy in. Can anyone point me off to a specialist ..a man who can set the tensioner up. A@