Need the serial number to answer.
Yes.
No such sn for a 38 spl
2015
Your smith and Wesson model 64-3 was made from 1977-1987.
Standard Catalog of Smith and Wesson
0-150 usd
100-1000 USD or more depending on specifics
10-1000 USD depending on specifics.
50-400 usd
1972
Seldom exceed 125 USD
Recommend you find a gunsmith or firearms instructor and ask for help.