Oh jeez.
Thats not a SMG-68. It either used to be or it was converted. Youd send in your SMG to the factory and they would converty it to what they called the 68 special. Then they made the gun for a time as well, no conversions needed. If that was an SMG, then that would be worth a bundle. But now thats its a 68 special its worth about what you payed or a little less.