In reply to craig1983:
Yeah if you are spending a few months over in NZ its a lot cheaper to buy a van (or subaru legacy like everyone else) rather than rent and sell it on when you leave for a similar price. also in terms of gear its really expensive (normally 30% extra) over here and there is a huge lack of range. the main mats you can buy here are BD and elderid mats for around $400+ NZD (approx £200) i just bought an organic mat and it was far cheaper to get it shipped over to NZ than to buy another mat in NZ. Also in terms of climbing in the south island there are not a huge amount of bouldering venues. castle hill is the big one and then there are a few smaller places like elephant rocks near timaru and the jardines in queenstown. At castle hill you can just rent mats at the hostel and cafe nearby in springfield for about $15 a day.
If you really were insistant that you wanted to buy a mat here the places online are - torpedo7, bivouac outdoor and on NZs version of ebay called trademe you can fing TOTA mats