ID this seat upholstery

[64chevmn]

I'm starting to re-upholster the bench seat in my 64 C10. When I cut the hog rings and pulled off the seat cover, I found this cover hiding underneath......it appears someone just put a new cover over the top of the old one. Can someone take a look at the picture and tell me if this is for a 1964 truck or from another year? I believe the seat I have is not original to the truck. Ignore the diamond pattern; that was the pattern on the cover I pulled off.