Model 18-2's were made from 1961-1967 The sn you list dates to 1973. You might want to recheck the sn.
@ 1978
1978
1967
No such S&W model number
your smith and wesson model 60-3 was made between 1988-1989.
K276694 was produced in 1956.
1969-1970
Without a serial number the best you will get is sometime after 1977
There have been thousands of Smith & Wesson pistols produced and the date depends on the model of the gun and then the serial number. Have a gunsmith or collector do an appraisal of the firearm and they will tell you the age.
You will need to call S&W
1960; 20-1000 usd
When was 38 smith and Wesson serial number 172095