The gun shop I work at just aquired a Ruger Single Six that I believe may be rather rare. Can't narrow down exactly which gun it is and am wondering if anyone here might know anything about it or know who to contact. It is an early 3 screw, factory nickeled, 5 1/2" barreled gun, wood grips with both cylinders in mint condition, may be unfired. It has the "fixed" drift adjustable rear sight and is in a non matching old red/black box. The gun is marked only "Single Six" whereas the box is marked "Super Single Six" 6 1/2". The book says that there were only 100 Super Single Six nickeled 6 1/2" guns with values up to $2500 but this is a Single Six with 5 1/2". The serial number is 4939XX. Any ideas? Thanx