If its gun/shooting related, they have it. GunBroker.com is the most reputable auction website that sells used and new guns. they also traffic in gun accesories and sporting gear, they have fast reliable checkout system that is safe and easy to use. Whatever you could possibly be looking for in sporting gear, this online auction is the place to get it at!
GunBroker.com is a lot like ebay. only it is more concentrated on shooting and sports of that kind, so that would include, knives, clothing and gear in general. And you the prices most often are well below (to coin a phrase) "bluebook" value.