I have an extra set of repros in a drawer or on a spare sling.
The finish and pin diameter-along with the actual metal used is different. I think I have 3 original sets on slings.

The rest are from Super Grades or Deluxe Model 71s. A 450 Alaskan Deluxe/Special Model 71 wears them here.
Surprisingly, I have owned Model 71 Standard Grades equipped with eyes for the detachable sling-fitted just like SGs or Deluxe models.
Winchester did not always stick to their own rules at the factory. The SG swivel sets are far and away better than any commercial swivels made to support a rifle in the field.