Importing AR parts under the 400 nzd custom thingy?

The price for 9mm AR rifles in NZ are crazy expensive, I'm talking 300% of the US price as well as difficult to find in stock.

However if importing you normally have to pay GST, however what if I buy AR parts, making sure that they each would fall under 400 nzd, would that work? (this link https://www.customs.govt.nz/personal...uty-estimator/ says there would be no duty for that)

Alternatively, I sometimes travel to USA, but I'm not sure if I can buy there and bring back to NZ because:
*I'm not sure they would allow me to buy AR parts in the state with just a NZ licence.
*Even with a NZ import permit I would be scared to bring on flight because my flight has a 1h stop in piece of shit Australia

(I have E cat license btw)

Just buy one off NZAR15, not a huge amount dearer, zero stress, and if it plays up (and 9mm ones sometimes do, majorly) Ken has the best after sales service going in NZ. Never met the guy, but he has sorted me out way beyond what he had to, on multiple occasions.

Plus it saves you ending up in a US prison. :P

You can bring stuff back but you will need a US export permit which costs $250USD for most parts (last time i looked) making the sub $400NZD import pointless.

Also you cannot buy firearms in the US cause they term you an "alien", Its not worth risking the consequences of just buying shit and sticking it in your luggage. US Border Security have all had their common sense removed and have zero sense of humor