Consider this Australian Travel Plan which offers basic but essential cover.
This Per Passenger policy will cover you up to 12 months if you are travelling within Australia and you only want cover for the non-refundable part of pre-paid travel arrangements or additional travel, accommodation and meals.
There is no cover for claims relating to an existing medical condition, luggage or a trip in excess of 12 months.
Australian Cancellation Benefits & Limits. Please read the PDS as conditions apply.