I have a couple of Ruger Single Six's that I won't part with. At one time I had 3 more blue New Model Single Six's (NIB) but let them go to friends and family.
Both of these guns have the extra .22 Magnum cylinders.
I bought the 3 screw blue gun (used) in 1963. It was never sent back to Ruger to be modified.
I bought the stainless new model in 1980 for my wife to shoot small bore silhouette matches.