Earlier, I was speaking from what happened to my 514 about 55 years ago. A Weaver center-fire type side mount with 3/4" scope top was used at the time, as I remember. The gunsmith was a "butcher". Haven't seen that rifle since 1961 and that experience when I was about 14, caused me to learn gunsmithing, so I could do better work than that guy.
I've since mounted scopes on other non-grooved receivers in the 510-513 series rifles, using Weaver Top Mount Bases, but haven't mounted any on 514s.