I would be surprised if an LBS didn't have one. If you get in good with them and they know they can count on your business they may throw it your way free. My LBS is pretty good about giving me small parts like that if they have them laying around (hub spacers, BB cups for projects, hose clamps etc.) Of course it gets expensive if they need to order things (just payed $20 to get replacement clamp bolts for my brake levers) not that they have a whole lot of leeway there.