A good KA (less than 100K miles) will run you back at least $500. They're not as cheap as they once were, they're not as common as they once were either. When I was in the market for a KA, a local shop here wanted to sell me a POS one for $350. I went to check it out and turns out it had bad...
There are a ton of scrapyards on North River Drive
Here's a map for your viewing pleasure.
Why don't you try calling first, use http://www.yellowpages.com/