Not too sure if qantas fly Darwin to KL, but I was talking with qantas a couple of days ago, and they charge $9.30 per kg from 100kg to 300kg and $6.80 per kg fro 300 to 500kg, plus $55 handling fees this end. And that is the same from Syd. London as from Syd. to South Africa, so work it out from there. There is also $106 Dangerous Goods Management fees.
One man's fear is another man's adventure.