Based on applicable tariff applied as per Australian
Customs - see their website. Plus GST on total landed cost including freight. UPS, Aust Post , Fedex etc will bill you for costs before they release from their bonded warehouse.
Re watermaker - check out Watermakers Australia.
www.watermakers.com.au
Stephens product has the advantage of using
parts that are readily available in Australia and the Pacific if you intend to
cruise this region for a while.
His pricing is competitive with importing (done the sums this year) I have installed his 160l/h system and happy with the quick
delivery, quality of the product and that Stephen answers the
phone if you have a question.

(No financial interest, just satisfied customer)