There are very few turbine corporate aircraft in NZ... I mean that there are only 7 jets in the entire country that I know of... the latest is a Westwind II. All of the planes that are there that I know of are Stage III aircraft.
I can't really speak for Aussie, but I know that there are many more planes over there. I would think not too many Stage II operations though.... and I say this only because RVSM has been in place there for a couple of years, and we all know how difficult it is to make an older plane cost effective during the RVSM conversion.
LB