I bought my 29-2 in early 1968, S282323. The price had increased from $105 to $125 in the couple of months from order to receipt!
Dirty Harry had not hit the theaters yet, and I have heard that the 29s were not moving too fast at that time. Only a letter will tell you for sure when it shipped and where.
There were many more than two Model 29s shipped in 1966. I don't have the exact number, but a quick check of the records suggests a number in the hundreds, if not more. Perhaps, only two have been reported by collectors? Revolvers finished in nickel usually make up about five to fifteen percent of those produced.