Contact Nathan Higgins of AFT in Maroochydore.
www.aft.com.au
Don't waste your time looking any further... he IS your one stop ATPL shop.
7 Australian subjects...
3 self study (get them to mail them across to you in NZ)
4 either self study (if you choose so) or better still, go across and sit his course, duration 4-5 weeks.... accommodation arranged nearby etc.
I did that. Best ATPL decision I made. You'll enjoy it and won't regret it too. Many others from NZ have gone across to him for just this purpose. You're not the first. Keeps your future work-options open as well.
PM me for any clarifications.
Good luck!