That's why I'm asking the question here....to see if the collective has come across such cassette. As I initially posted, there is no reference schematic to this Shimano model on their web site. There is a lot of variance to their 8 speed cassette offerings.
I thimpk that it's from an early '90's Ultegra setup. Certainly Shimano's current 8-speed offerings are not as extensive as back then.
Silver painted? Are you sure? Not plating or similar finish?