Many Supertargets (introduced 1963) had no scope rail. But some did, especially the early ones, such as the X-prefix serial numbers.
The post-73 Anschutz sight ones mounted the sight on a rail. I think perhaps a different rail from the usual MkIII rail.
Supertargets came with, at various times, PH16M, PH17B, and Anschutz rear sights.