Just ordered some of these. Looks like a pretty decent deal. They are police trade in magazines for $11.95 each. Shipping was $16, which I thought was pretty high, but I ordered 5 mags so it came out to $15/mag.
http://www.aimsurplus.com/product.aspx?item=MGLK21
http://www.aimsurplus.com/product.aspx?item=MGLK21