Amazon AU has it at $57 with free delivery but if you need it urgently like I do, Officeworks and Harvey Norman has it at $58.
JB Hifi $59, potentially further 5% off if you can get discounted giftcard for JB Hifi.
I'm currently using this model for my home computer, pretty decent and nothing fancy (no backlight etc). Works well and comfortable for me. Only downside is that one of the keyboard legs broke and I had to superglue it back.
Officeworks link here: https://www.officeworks.com.au/shop/officeworks/p/logitech-w…, and it's priced at $58, which means you're very likely to get them to beat Amazon's $57 by 5%, bring it down to $54.15.