Another thing you might consider is checking ebay for sellers who sell things for other people. I know there must be at least two people doing that with classical records out of NYC; there were a few summers ago when I was buying alot, anyway. I got some very good deals that way.
When I was in Westsider Records a couple of years ago, I found it to be an excellent place to shop for classical, especially opera. The rare stuff was priced accordingly, but most things were very reasonably priced, and there was a great deal of it. So I would check them out, too, as well as Academy.