Jim, if his gun is a no-lock, I believe it will be pre 2002.
Well, you're right!
I went back and looked under the model 317 listings itself rather than the serial number listing and it shows some "LGT" prefix guns being made in 1997.
Just an FYI, but S&W has been offering some "no lock" J frame models for the last couple years, which is what I assumed this was.
Of course, you know what they say about assuming...