Congrats on the find! You don’t see these very often.
I came across one recently as well. I replaced the stocks with a set of smooth target SB stocks and it handles very well.
There was a limited run 681-4 PC Quadport Lew Horton with 7-shot and 3” bbl made in the early days of the Performance Center.
This is one of my favorite guns.
Cheers,
686PC