I have a pair of GunCon guns for the PS2 that came with Time Crisis 3. Works great. You can get these to work with MAME if you download the WinGun drivers. I've gotten them to work in MAME but my new machine doesn't do composite TV out, so I don't need them anymore. Great for someone's gun cab project. The game is also included (as well as the original packaging) if you want to use them with your PS2.
$25 shipped in the US.