This can vary greatly on the manufacture date, which you can tell from the serial number. If it was made between 1954 and 1957 it could go from $225-850, and if it was made 1957-1986 it could go for $225-495. This all depends on the condition of the handgun.
@ 1964-5
Need the serial number to answer the question
1970 to 1972
1975 or so
50-500 USD or so
@ 1976
100-800 USD; can't date without a serial number.
With the serial number that you have provided,your Smith and Wesson model 28-2 Highway Patrolman was made in the year 1973.
1978
50-500 usd
1975-1977
50-460 usd