Bay of Islands berthing

[Budawang]

I belong to a cruising club which is looking to base a 40 foot catamaran in the Bay of Islands region of New Zealand. The boat will arrive in NZ in early December 2015 and depart in April 2016. During that time it will be used by club members, but will require overnight berthing every two weeks to allow for crew changes, cleaning and resupply. At a pinch a mooring might work provided there is good shore access and a tender service.

Unfortunately, the Bay of Islands marina in Opua can't accommodate us as they will be busy expanding.

Does anyone know of other options in the Bay of Islands or nearby?