"Sales tax" in Australia is non existent, I think you mean the
GST here & it applies to consumer electronics ( & that of course includes computer components) is 10%... BUT there is the sellers markup on top of that & its competitive in this area.. very!
Apart from that & back to the topic here, my view is that computer component manufacturers will be looking for markets to "dump" there product on to & the USA's upcoming tariffs will encourage them to seek other markets & that includes even smaller markets like Australia... anything to move product out asap. That's a view also shared by some economic experts here in Australia at the moment.