I just get mine from my local butcher, but you can get them at woolies too I think. The brand I get is A&T Trading and they are in a black box with a pic of the prawns on the front. It's a 1kg box and they have no heads, so it's a genuine 1kg kwim? I got mine for $34. They have a website too - google attrading and it's the 7th listing - they might know of VIC distributors.

ETA - you're also approved ROFL.