I think I got a good one at my local gun show today. A factory nickel model 10-5, 4 inch pencil barrel with original magna stocks. I would put the condition of the gun at 98%. Came with the original box which is not in very good condition and the paper wrapping. No tools or other paper work. The serial number C8333xx puts it in 1966/67. It has been fired, but very little.
Are you sure the grips are original? With that date they should be diamonds. But as always with S&W you never know.
You may just be correct about the grips. The diamond wasn’t dropped until 1968 and there is no serial number written on the inside of the grip…. Oh well, at least they are in perfect condition.