What I did was send the money as AUD, and not let the Australian bank do the conversion, but a Swiss institution.
www.wechselstube.ch or .com
(do a search on the forum, or check their faq if you are interested).
Reason was simple, their rates are much better, as the spread is very low (0.75% one way). From memory, there is no fee for receiving the money, so you need to pay the fee from the Australian bank.
My credit union charged more for this, as they do not like sending AUD overseas, as they don't gain anything. It was 35$. But perhaps Westpac or Commonwelath allow you to do an online transaction overseas in AUD? Westpac used to charge 10 AUD but that was ages ago.
Anyway, using the above method, you would only pay charges at the Australian end (the sending part).
I am not affiliated with those guys, I just like their setup.