Hi,
My experience is limited to buying Michellin XM2 tyres, but I found a crowd called Discount Tyres on the Great North Road in Grey Lynn to be cheaper than most and very competitive compared with the great price I was getting them for elsewhere in central North Island. $378 for two tyres fitted and balanced 205/15/65 on the 1st of September 2014. Great service too!
I looked them up and they have 5 branches in Auckland.
Put them on whichever axle you like.
Discount Tyres
352 Great North Road, Grey Lynn, Auckland 1021
Telephone 09 360 7070