It's been much cheaper before, but still a pretty good price for a Koala mattress delivered (Queen is currently $1190 on their official website). Unfortunately the King is not part of this sale.
Double: https://www.costco.com.au/KOALA/Koala-Double-Mattress/p/1697…
King single: https://www.costco.com.au/KOALA/Koala-King-Single-Mattress/p…
Single: https://www.costco.com.au/KOALA/Koala-Single-Mattress/p/1697…
Any good ?