With the increase in Apple Airtag pricing, I was able to find this pricing. Not as cheap as the Costco deal (which is out of stock), though you can pick it up free in Sydney, or pay for shipping.
Using Westfield online via Wireless 1, their $175 price drops to $150 after using WD25BLOOM as promo code.
I rang Apple and they could use the Wireless 1 offer (as they have physical stores) to drop their $165 price by 10%, to $148.50, since I was happy to pay an extra $6.72 to get all 4 engraved.
$137 delivered last week.