Welcome to SWF.
Does your gun look like this with the stocks mounted?
kr-st i.jpg
If so, you have square-butt target stocks on a round-butt gun. Those are not the original nor correct stocks. A picture of your gun would help determine exactly what stocks are on it.
The letters and numbers are S&W part numbers and have nothing to do with the "production date" of the gun. Post the serial number (including any alphas) on the butt of the gun and we can give you an approximate factory shipping date.
The stocks that most likely came on the gun are "magnas" and they leave the gun's grip frame exposed on front, back, and bottom.
SW10-7 gf.jpg
With those stocks, the gun would look like this one.
SW10-7 ght-r.jpg