From memory......
.....NZ signed a contract with Kaman Aerospace in June 1997, the same month as the Aussie deal was put to paper.
The big difference is that the RNZN Seasprites have already entered service in the RNZN. They were purchased on the basis of how many were needed, and not how many can they could get for the money.They were also not a hung with unproven and state-of-tomorrow equipment but a previously tested model that was already operating successfully in the United States.
New Zealand looked ahead to a useful operational life for the planes of 25 years. For this, new rather than 40 year old refurbished air frames, were preferred. And this provided certainty in build scheduling and costs.They cost more than the antique air frames [some more than 40 years-old] chosen by the Aussies. About $3 million additional for each one, but in the end it was a more prudent way to go, and they've been in service for five years!
God only knows what the Aussie deal will cost by the time Kaman sues them.