Holy crap that's expensive! These are on the stock B13 14" rims? On discounttiredirect.com you can get falken ziex 912's for 55 each (the 512's are 52, but you don't seem to like them), free shipping, and most places will mount them for 15 or less each. At 15 each to mount/balance, you're looking at $280 out the door. And don't be so sure about the junk yard solution. You may have to cobble together 2 different tire types, but they will have plenty of life still, you can even check the date on the tire to make sure they are recent. I thought you were just looking for a cheap solution until spring. If you're going to spend that much on the Bridgestones, I guess you are looking for one for a while? Here's the link to the falkens:
Tire Products - Discount Tire Direct