As has been pointed out below you can order online for $5 cheaper and they might have the SE available. This would be Australia wide.
Went to Costco Docklands today, yes you do need a membership.
Apple Watch Series 6
Blue/Navy 40mm - $575
Grey/Black 44mm - $625
Apple Watch SE (sold out)
But costs were
Gold/Pink, Grey/Black 40 mm $410
Silver/white, Grey/Black 44 mm $460.
Apple Watch 5
space Grey 40 mm $450.
You can return electrical stuff within 90 days, if you don’t like it.
You will need an iPhone with the latest IOS to set the watch up.
Today wasn’t too bad at Costco, yesterday was bonkers. All the people who could now travel 25 km. .