Totally depends on weight, plus type of delivery you want - fast, slow, carrier pigeon. You can also add insurance to the cost, if it goes missing and you want to replace the stuff.
I usually pay a high cost, (fast air delivery,+insurance, so I can track the parcel) because by the time I get around to posting gifts etc to Oz, then birthday has passed and so I feel guilty. I've paid over 100Y for quite a small box because of this.
Sorry - that's not much help.