EC31 said..
Apologies, I was answering the original question by someone who is based in Canberra relating to a boat on Pittwater. You can go to any Services NSW office (ex RTA mostly) to do maritime, the closest will probably be in Queenbeyan. It is probably a very large one, but the level of knowledge relating to maritime will probably be fairly basic as they are a few kays from the water. Pay your bill, not a problem. Ask for regulations relating to moorings and you get an eye roll and a request to take a seat while they find someone who knows something.
When I advised RMS of extended leave for my Pittwater mooring, I was advised to send the documentation (and the resulting follow up) by e-mail to Gosford. The last response came from a lady in the city using the Gosford E-mail address I posted above. YMMV
Hornsby Maritime office was across and down the road towards the rail line until recently. It is now part of Services NSW Hornsby.
There's an oxymoron "Service NSW"