VM is correct. If the stocks have stainless circle inserts (washers), they are not original. If they have blued stamped steel inserts, they could be. The change to stainless happened around 1973.
Most post-war .357 Magnums came with Magnas like these.
They also came with non-relieved Targets. I lettered mine and it lettered that way. Yes, they are still on it (when I don't have the Executioner's stags on it).