Since the Supergrade eyes are wider than, say, Uncle Mike's QD swivel eyes, AFAIK you'd need to search for a set of gennies.
(SG's on left, normal on right, below)
While repros are made/available, IIRC they're only available as sets, with bases, and not swivels-only.
I think I've seen some gennies on fleabay - you might also check there for some.
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