It's unrealistic to expect a bike shop to have in stock every single piece of gear for every single type of bike for every single different manufacturer from every single era. Shops have to buy the product, and it's very risky for them to buy product that they may not be able to move.
I support my LBS as much as I can. If they have what I need, great ! If not, can they get it to me for a reasonable price? If not, then thanks guys but I'm going to try to find it online. Give me a call if you come across part xxx in the next few hours before I order.