We just tend to buy stuff from Ali Express because they are free freight to New Zealand in under two weeks, while American places like amazon charge up to US$50 courier, often take longer, and sometimes totally stuff up the packaging! (my favourite was the time they sent us a box of stuff but forgot to tape it closed!)

So the price of the Pi itself is not that critical - I think we paid about $150 for our first one from England, so $37 is a bargain