Model 61 Winchester date of manufacture?|Winchester .22 Rim Fire|Forum|Winchester Collector

I have a model 61 Wnchester s,l,lr gun with a serial # corresponding to 1962.  The gun has a metal butt plate and the frame is grooved.  My question involves the date of manufacture as I graduated from high school in 1961 and I hunted with this gun during my high school years in Kansas.  I clearly remember hunting jack rabbits to sell to a mink farm during that time.

I know that my father returned the gun to Winchester because it would on occasion fire when the bolt was closed without the trigger being pulled.  Could this return have resulted in the exchange of my gun for a “new” gun?  If so how does one explain the metal butt plate?

I am old but not crazy (yet) so please do not discount my memory.  All information and advice appreciated.

jlb