R/S within a shield on 14K gold ring

by Sally
(Philadelphia, PA)

What does the R/S symbol mean that is stamped inside of this ring? I think it's a maker's mark but I can't find any information about it. I believe the stones are blue topaz (main) and diamonds (side).

There is also an etched number on the other inside edge, but it wasn't worth trying to take a picture. I think it reads "R3294."

I'd appreciate any additional information you can provide.