1981....probably Seahorse Yachts in Station Road, Seven Hills, Sydney.
My family had a boat built by them in 1980 and the Adams 31 was part of their line then...choice of centre or aft cockpit.

Have a good look at evidence of the lay up of the hull...very dodgy operators...we basically had to have the hull rebuilt around the keel area because of osmosis in the first couple years.

Should have been addressed if the boat's still kicking around after all this time??

Good luck
Trace