In the past Porsche would tell you to do one if you don't have history of buying brand new not so exciting models from them.
However Porsche bubble has truly burst now on their new models, even the GT cars and even some RS models.
So here in the UK if you wanted to buy brand new it is now possible without buying history, you have to ring round all the dealerships and see if one has a spare allocation or believes they can get you a car. In the UK if they believe they can get you a GT3 they request a £10,000 refundable deposit, probably similar in NZ, so first step ring round all the dealers, you may get lucky.
If that fails then consider buying q 6-12 month old one from a specialist, not sure on market in NZ but try to avoid paying overs as those times are over now on Porsche apart from the very exclusive RS models potentially, though here in UK Porsche has got Spyder RS coming out there ears and its quite easy to buy and spec one brand new at moment.
Alternatively buy a 992.1 GT3, plenty of approved used about and still a fantastic car that you can now get for fair money and not pay overs.
If your not fixed on a Porsche, for 175k there is far more exciting road cars you can buy to be honest, but particular older stuff, newer stuff really is just a numbers a game now and has lost a lot of what makes driving fun.