https://uk.gamersgate.com/ has christmas sales right now. You can check out other games if you want but I'm creating this post specifically only for watch dogs 2 (and yes the uPlay key you get can be activated in Australia, I bought the standard edition and it's all good). This is by far the cheapest Watch dogs 2 price that I've seen ever since the game was released except if you take into account those eBay listings (but you can't guarantee if those eBay keys will work because of the region lock that ubisoft imposes)
All pounds to AUD conversions are based on PayPal exchange rate where 1 $AU is equal to 0.56 ish pounds
Standard version [~AU $44]:
https://uk.gamersgate.com/DD-WATCH-DOGS-2-EMEA-RELEASE/Deluxe Edition (it's not worth it to be honest) [~AU 48]:
https://uk.gamersgate.com/DD-WATCH-DOGS-2-DELUXE-EMEA-RELEAS…Gold Edition (this is the version that you have to buy if you want the season pass included) [~AU 69]
https://uk.gamersgate.com/DD-WATCH-DOGS-2-GOLD-EMEA-RELEASE/
Feel free to create another post if you can see a good deal on other games on the website, cheers mate, and MERRY CHRISTMAS!!!
The standard edition is AUD$42.86 on Uplay (providing you have enough Uplay points to redeem a 20% voucher).