It was started in 59 and shipped in 63 without a serial number.
The date code is LFK
http://www.remingtonsociety.com/rsa/questions/barrelcodesI have older, newer, cheaper, more costly, bigger and smaller 22 rifles, but that is my go to killer 22.
I tag guns to try to keep track of them. I have been buying guns for 53 years and my memory is not so good.