Mike - fantastic S&W pairs. Thanks for sharing them. I'm sure you spent a ton of time to track down such rare and interesting variations.
Probably the best "rare pair" I have is "first year magnums" - a 1935 357 Registered Magnum SN 46696 REG 492 which shipped 9-26-35 and a first year 44 magnum, S130937, which shipped 4-2-56.