There's a 2 for 1 sale currently at K-mart. I picked up Jungle Ripcord, CS Duke, Desert Viper, and the Crimson Neo-Viper for $15 plus tax, which is fantastic. I might go back and clean out the Elite Vipers and Ice Vipers, since this is the cheapest I've ever seen them.
I also scored all the WM Battle Stations. The LAW and maybe the Heetseek (MMS) are a little outdated (screaming Cold War), but the rest are great.