Charnwood fasteners (in Loughborough) can probably help if you are. I just collected some pinch bolts for my kwak track bike and a few for the duke all in stainless for 2 quid. Pro bolt wanted 14 quid just for a set of 4 pinch bolts plus postage!
Do they have a website, or is it good old fashioned pop in and hand over strange bits of paper and round bits of metal?
They're pretty old fashioned but I think one of the young lads mentioned if you e mail them they will reply to queries or sort a load of nuts bolts etc for collection.
not open sat mornings which is a bit of a pain, but if you can get there during normal business hours they have very competitive prices for mail order stigs fasteners are good
Our local fastener shop has an amusing name. Has everthing from the popular sizes to the wierd stuff. Construction Fixings, Bike Bolts, Car Bolts, Stainless Screws, Wood Screws