Vintage 1978 910 Puma Prince Stainless Folding Stag Knife

This knife has been in the box since new. Occasionally handled but never carried or used. It was purchased as a Xmas present in 1978.Puma 910 Prince Folding Knife with green and yellow Puma box and certificate. Stag handle with stainless steel blade 3.75 inch (total length 8.5 inch). Puma website confirms age. See screen shot. Closed knife 5 inches, very nice quality feel.
These continue to increase in value. There is a small mark , like it was done on purpose above the A in Puma on the last picture. Has to be from factory also. This is a handmade knife.