A third (or fourth) thumbs up on audio images in SF. I just bought a pair of Dolby SR rack units there for $100 each.
Leo's Pro Audio is OK, with some high end stuff. If you go to Bananas at Large in Marin (where I live), talk to Vadim - he really knows his stuff.
I'd also like to mention R&M Pro Audio on 10th st. in San Francisco. They stock lots of stuff for the film post community - reel to reel tape, shotgun mics, etc, as well as good high end gear for recording music.
Be sure to check out Craigslist while you are here:
www.*************** - they have a music gear section with free postings. You might get a bargain on something from a private seller. Finally, there is Dan Alexander Audio and Dan Dugan Sound Design, who both sell vintagey kinds of things. My take is that Dan Alexander charges too much in general, but you might find a deal.