.45 acp

The cheapest you are going to find and still get a quality piece are going to be Taurus. Colt, Remington, Springfield are all going to demand top dollar, regardless of age. If you want a fair priced great shooter and top notch customer service, the Taurus PT-1911 is the way to go. Here's 2500+ to choose from -- all manufacturers.

http://www.gunbroker.com/Auction/Se...0&Timeframe=0&Keywords=1911&Cat=3026&Items=50

And stay away from Rock Island and Umarex -- they are cheap and you get what you pay for.