Actually, 8K serial numbers were spread out over a three year period; 1975-1977. Those made in 1977 started with 8K80001. So 8K949xx would have been produced that year, not earlier as the SCSW 3d would suggest.
Great looking model 17-3. I once got the chance to shoot a vintage model 17-3 at a range. Without a doubt the finest 22LR I have ever handled. I asked the owner of the range if he would consider selling the revolver to me. He said no way. I am should you are enjoying your revolver.
I was just looking at some records of gun purchases. I bought one just like that in January of 1975. I still have it. Unfortunately, I have not shot it since Thursday. It is one of my all time favorite guns. Enjoy yours.