I hear in L.A., you can find a GS3 dealer on a few street corners. Maybe you could score some for me? Watch out for the cops though, if they find you've got too much polyphony, you're going in the slammer.
Look for sweetwater sales at Christmas time, that might be a good bet. Also, you could see if you can find a copy of GS 2 cheap, and un-registered and than upgrade to version 3 for a small price. Just some suggestions.
Are the cheapest place to get GS3 as a competitive upgrade. I just purchased my GS3 orchestra from there for $329 shipped free, as a competitive upgrade from Kontakt. When I called both these places they told me that you do not need to surrender your Kontakt license.
But if you do not have a competitive upgrade try this link, this is where I found the lowest price. $429. But I cannot say more than that since I've never bought from this company before. (floridamusicco.com)