Unfortunately thats the only sighting(although I have only heard of it on one website and the news), and its in the Poor Knights - so it cant be taken(Marine reserve).
However, since it is so small it has probably(/hopefully) been overlooked in the past. It looks damn cool though!!!
Have you logged onto FNZAS? RC's great but not very practical for NZers in terms of trading ect.
There are a couple of importers on the NZ board - the NZ deltec guy and the guy who imports pretty much all the fish/corals. Definately ask on there, there is a sticky at the top of the saltwater column that might have some places to get stuff.