Mate NZ is the place for all sorts of beer you lucky *******. I tried a heap over there (Wellington), most of them from local or NZ craft breweries.
Sour beers that I recall were very good and you should be able to find locally are- 8wired (this was a belinner Wiess from a hibiscus infused randal- full beer wanker but also fantastic), Fork and Brewer do some great sours, Cherry 2000 gose was my favourite. Macs do a raspberry berlinner wiess- that wasnt bad. Toll I think, was a Norwegian brewery that was in many places and specialised in single hop sours. sur saison and sur Citra were 2 that come to mind- very sour but the nose on them was amazing.
There are loads of good brew pubs and breweries over there. Get to a few and talk to the guy behind the bar- he will know his stuff and will sort you out.
Also worth noting, sours aint sours. If the first one you have is too sour for your liking, try another that is less sour. Gose is a good entry level. Don't have one and decide they are shit, have 4 or 5 different varieties and if after that you haven't found one that you like then decide they are not for you.