Well you have to understand that a shop lives by selling new stuff and selling the parts for recent bikes. They sell "universal" accesories plus clothing and gear and that's it. If you mention "cruiser" they will show you like 10 different brands of cruisers from electra and nirve to some unknown wallyworld like brands with gaudy colors and stupid themes for college boys and girls because they think that "looks cool", they don't know any better but that is their demographics. I have been going to LBS recently and I have never seen such a huge collection of new ugly cruisers.
No shop will actually give much attention to old stuff just basic maintenance, unless the owner is also crazy about customs. I never look into those shops to get old parts, just to get ideas of the newest trends. I buy my parts online on Ebay or specialized vendors that have what I am looking for, its not hard to find info online. If you need labor, you better show up with the parts already.