Welcome, and a very nice example of the Perfected! The majority of these I have seen were in nickel and many survivors are heavily worn.
Regarding the serial number, S & W never shipped in order and I recall reading with this model that they specifically shipped later numbers first to confuse their competition as to how many units were being sold. So the only way to be certain of its factory "birthdate" is a letter of authenticity, as seen in post #3.