Yes, I believe it's a clone - but nicley done.
For me its very important to proof to our DMV guys that such a dressed up car was available back then. It would be even easier if I can proof to them that the super stock package was a option which would not show up in the VIN. If thats the case all I need is to present that the parts used on the car are the right parts from back then. I have the original super stock brochure with all the part numbers...