Guess you could still say this one is based on the Model of 1953 .22/.32 Kit Gun. Mine S.N's from about 1980 and is not pinned. However the SCSW lists the date of the engineering change to eliminate the pinned barrel as 1982.
Anyrate, added this little 4" J-Frame .22 cal, Model 34-1, Nickel Model to the stable today...
Cute little revolver you have there. I always wanted a nickeled one in 2-inch, round-butt, but the few times I have seen one in nice shape, I have had other irons in the fire. Congrats on your new purchase.