You are off on the dates. The date code on the barrel flats will be a letter and a number like G.1=1970. In 1970 the gun listed for $134.50

Here is the info. You can also find the maker's marks on the barrel flats. If you pust forward on the front trigger, it should move; hinghed trigger.

http://personales.jet.es/rafa/b_punzones.html