23% off on Amazon. I haven't seen it this low before. According to BrickHawk it's $479.20 at Big W but it's currently OOS.
Unfortunately CashRewards and Shopback aren't valid on the Toys category.
I used Prezzee giftcards I've been stocking up on for ages.
Other HP lego on sale:
76389 Chamber of Secrets $179: https://www.amazon.com.au/LEGO-76389-Anniversary-Collectible…
76398 Hogwarts Hospital wing $55.20: https://www.amazon.com.au/LEGO-Hogwarts-Hospital-Buildable-7…
75948 Goblet of fire $95.20: https://www.amazon.com.au/LEGO-Harry-Potter-Hogwarts-75948/d…
I'm sure there's more sets — just type harry potter lego in the search bar.
no limit.