Hull Identification and production year

Hello, I purchased a Hobie 16 recently and have been trying to identify the year made. There's no inscribed serial number on either hull. The only ID I can find is the number "307" stamped into the outside of both of the forward pylons. I interpret this to mean the boat was made between 1970 and 1973 before Hobie went to the 4 digit or rear hull serial number placement. Comments/Thoughts appreciated.