It is a genuine Smith from 1978. My favorite story is how I acquired it.
I was stationed at Mtn. Home AFB, Mtn. Home, ID. I was helping a friend move from the base to Boise, ID, about 50 miles away. It was late and I decided to spend the night with him rather than drive back.
So I went to a drug store to buy a toothbrush and some toothpaste. While there, I noticed that this drug store, a CVS or Rite-Aid like place, had a little glass case in the corner and they were selling handguns and knives.
With my toothbrush and toothpaste in hand, I went over to look at the offerings. The cashier said she could ring me up there, and asked if there was anything else. I saw the S&W Model 19, 4" barrel, at a great price, so I said "yup, that one, please."
This was 1978, so there were no waiting periods, no background checks. Filled out the federal paperwork and walked out with a toothbrush, toothpaste, and a handgun.
Only in America (or used to be...)