Ah, sorry, you said IRA so I skimmed over the Australia reference. I was not aware standard IRAs were available in other countries, either, I thought the IRA was a US specific retirement account. If there are no ways to early access your country's specific retirement accounts, then post-tax investments may be your only option. You can open a brokerage account with Fidelity or Vanguard and buy index funds or ETFs.
You may have more luck asking for Australia-specific options in Investor Alley (I recommend putting Australia in the subject line) or in the Australia specific Tax sub-board.