The 29-2 was the variant produced for the most years, from 1961 to 1982. To find what year a particular Model 29 gun was made, it is necessary to telephone Smith and Wesson. (For Remington or Ruger or Winchester, etc, you need only do an internet search for "Winchester serial numbers" for example, and you can quickly find what year a particular gun was made. This works for almost every company except Smith and Wesson.)
27 years old
1983-1988
Your serial number indicates that your Smith and Wesson model 59 was made in the year 1975.
31 yrs old
Not a S&W model number.
no serial number provided
Impossible to answer without a serial number.
25-33 yearws old
1977
@ 42 years old
Your serial number indicates that your Smith and Wesson model 59 was made between June of 1978,thru 1979.
36 years old