Ordering online is the easiest way to get a copy. Bibles are $30 each, and this price includes shipping costs.
You can also call 09 263 5919.
You may find the following links helpful:
The word of God in the Maori language. A faithful reprint of the original 1868 translation.
Trinitarian Bible Society NZ IncPO Box 137025, ParnellAuckland 1151 NZ
09 263 5919
Trinitarian Bible Society Australia47 Queen StGrafton NSW
+61 2 6642 8880