Citation(s) from the GunPolicy.org literature library
Alpers, Philip and Conor Twyford. 2003 ‘Stockpiles and Trafficking in the Pacific.’ Small Arms in the Pacific; Occasional Paper No. 8, p. 18. Geneva: Small Arms Survey, the Graduate Institute of International and Development Studies, Geneva. 31 March
Sir Thomas Thorp's 1997 Review of Firearms Control in New Zealand estimated that New Zealanders owned between 700,000 and one million lawfully held firearms, and between 10,000 and 25,000 illegal firearms.
This is the largest per capita small arms stockpile in the region.
Given the rarity of smuggled firearms (see below), it seems that demand for illicit guns in New Zealand is largely satisfied by the legal stockpile.