The big gun, the one that folds up, was sold on ebay and the seller had no idea what it was for the first 5 days of the auction. I didn't either, but I knew it was pretty interesting looking and obviously a hero piece. I have the auction photos on my hard drive somewhere. I'll dig them up. They were very good.
You might be thinking of the Sid Mead gun used for Special Unit 2. I don't believe he designed the tekwar guns at all.
They kind of like the same design to me.
Well Tek War started as a Marvel comic called TEK World with Bill Shatner drawn as the lead character.