...can i buy a reproduction sheet...
No. A reproduction would be meaningless. Keep the money in your pocket.
Sometime nearing the end of 67 model year production, assembly line staff began gluing a copy of the Corvette Order on the top of the fuel tank driver's side as an aid for identification. At that point, the VIN had not been attached to the car. The stickers were never meant to be permanent and are usually not visible with the body on the car. Over time, a tank sticker could have become unglued and disappeared, or part of it could have disappeared. or if still there, whole or in part, could now be illegible. It is factory documentation worth having if it is still there after all this time and if you can read what is on it. If you work with the fuel tank collar and a good light source, you
might be able to see enough of it to realize something is there. I do not advocate going to all the troulbe of dropping a tank just to see if something might still be there, but, if the tank otherwise needs to come out, it is certainly worth taking a look.
Copies of build sheets have been found tucked in the wiring behind the speedo/tach; tucked in the wiring behind the center cluster, behind either kick panel, tucked in the springs under a seat, and under the carpet in the rear storage area. All of these locations are rare and out of the ordinary. This is not to say you would be likely to find anything in any of these areas if you looked, but build sheets have turned up in places other than the fuel tank.