Not that I know much at all about current NZ laws but I'd have thought aminoindan and it's methylenedioxy counterpart would both be covered by the NZ equivalent to the analogues bill. However, as seen with the recent methylone/ ease issue, NZ laws may not be that rigid and in such cases may require specific listing.
Surely if an inquiry was made to the appropriate government department stating your wish to seek legal advice regarding importation of particular pharmaceuticals, health products, research materials or whatever you classify these products to be, then someone should be able to point you in the right direction. After all, when it comes down to it, all you're trying to do is to make sure you operate within the law.
If you haven't already done so, try searching for MDAI on this site. There's a few bits and pieces.
Please appreciate that while it is claimed these substances may not be neurotoxic in the same manner that some amphetamines and MDMA are thought to be, it doesn't automatically give these drugs the green light.
Before deciding to ingest new or relatively unknown substances, make sure you appreciate the broad range of risks involved. Also, if you decide to take either of these chemicals, always be as sure as possible of the quality of the substance. I'd never suggest buying from online RC traders. Such products should at the very least be purchased from a legit, reputable company.