if it is sent bog standard post, then you shouldn't have to pay anything, as the postal limit is i think $1000 before a formal customs entry is required and customs will not pursue gst/duty if the amount that would have been recovered is less than $50. theoretically, they could recover on a posted item worth $500 aus or more (including post), but in my experience *this is not a statement of what your circumstances might be* I have never been asked to pay duties, despite having bought several expensive camera lenses from the US and having them shipped USPS. using a freight forwarder changes the equation as they will raise a customs entry for you (if the value is over $200 from recollection) and charge a handling fee and whatever customs decide to charge to raise the entry. if you ship express one would assume that it is an air import (unless you can point out an express boat), an entry for that would be $27.10 customs charge plus the ff handling fee. it's an awesome business isn't it. you charge the guy to send it, and then the guy at the other end to receive it. win both ways!