Need the serial number to answer the question
100-400 or so
IF IN CLEAN CONDITION, ABOUT $500
1970 to 1972
1975 or so
50-600 usd
50-500 USD or so
You will have to call S&W with the sn to find out.
@ 1976
100-400 USD depending on condition, box, accessories, papers.
No sn = no way to answer. 50-500 uSD
1978
The best that I can do is say that the smith and wesson model 28-2 was made by smith and wesson from 1961-1969.