USM8A1 VIZ Scabbard and Knife - Help!

I bought this knife at a yard sale, because it looks old. The Scabbard is marked USM8A1 VIZ, and has a metal belt hanger. I found them online, but every one of them has a fabric belt hanger.

The Scabbard is 7 1/4 inchs long, and the metal hanger is 3 1/2 inchs. Makes the total length of the scabbard 10 3/4 inches.

The knife blade is 6 5/8 inch long, and the overall length (blade + handle) is 11 3/4 inches.

The knife is in very used condition, and I can't find any markings on it anywhere. Please take a look at the picture, and any information you can give me about the scabbard or the knife is VERY appreciated.

Thanks!