Any autoparts store should be able to help you out.
Price here, compared to imported stuff is the issue.
Both these places have them ... If they wont sell direct to you ... just ask for the nearest store that stocks their gear.
http://www.efi.com.au/index.php
http://www.afi-australia.com.au/default.aspx
Qld (bris) probably has similiar wholesale stockists.
Correct part supply is helped if you can quote the numbers stencilled on the side of the crank angle sensor.