I've looked at many used Single Sixes. A lot of them were well used and they still wanted $275, $300, $350 and $375 for them. I finally found a Super Single Six, 5 1/2" barrel, at a local gun show and I got it for $350 OTD. It is like new. With both cylinders. A 1989 year model.
I wish I could have found one in good condition for a lesser price, but I couldn't. I guess the availability of reasonably priced, used Single Sixes depends in what part of the country you live in.
For example: One of the area pawn shops has a Single Six, without the mag cylinder, no box, no paper work, no bluing to speak of (reeked of the smell of cold blue), and one of the grips was split. Traces of rust were visible in one of the chambers!! $270. I offered $100 for it and they were insulted. They then offered to let me have it for $220. As far as I know, they still have it.