I'm not a guru on FEG numbers, but if the MarkII says APK MK II, and all blued, it is older and all-steel.
If it is two-toned, then it is newer, has an alloy frame, and is significantly lighter. I believe that's the SMC.
I've got an APK Mk II, all steel. Nice pistol, but I wish I had the lighter alloy SMC. That is a NICE pistol.