When looking for old stuff, it's worth just going into shops and asking. Any shop that's been around for a time has an area containing 'stuff' and you can't tell from the shop front. I have a lovely track frame from a shop that out front shows no interest in such stuff ( had a choice of two). I've picked up Shimano 600 bits and some lovely vintage bars from another shop that's been around so long that old stock has slowly been shifted to the loft. I picked up some bars, quill and aero brake levers from a relatively new shop ... which had an old racer that'd just been run over by a car.

No harm in being cheeky, just go in ask, the worst that can happen is they'll say 'no' - if you can't handle strange looks, you shouldn't be riding fixed gear in the first place