Not far from Auckland is beautiful Coromandel to the south east. There's a b&b who have a garden obs.
http://www.stargazersbb.com/booking.html Not cheap, so I never stayed there :'( . Don't know your purse.
These questions turn up once in a while. I wonder whether astronomy club members down under and in GB/Europe could begin multilateral negotiations.
.. a trusted UK club member could then just email in advance to an Oz/NZ club and either get volunteers for a viewing night with their gear at their location, or rent a travel setup for the duration of the holiday, insurance and bond like with a rental car.
Same vice versa.
No membership since x months/1 year? no rental gear.