I just returned from a couple of weeks in Kiwi Land and found a few sirens in various towns. I also heard a single blast from the Port Chalmers siren for a fire call, probably cut short because there was a cruise ship docked next to the fire station. It had a turbine-like wind-up sound right before the actual wind-up, just as in this video (not mine):
http://youtu.be/BHW_fNXUZSc I was also in Australia but didn't see any sirens there.
On the South Island:
Port Chalmers (east of Dunedin, at fire station)
St. Leonards (also east of Dunedin, west of Port Chalmers, at fire station)
Akaroa (on a hilltop above the town)
Picton (I could only get a shot from right under it, behind the fire station)
Another shot of Picton
On the North Island:
Napier (on the roof of the public library)
Tauronga (street clearer in front of the main fire station)

Lex orandi, lex credendi, lex vivendi.