^ They are available in Australia.

From the Where To Buy section of the Ultimate Game Card website:
Australia Post
Big W
Toys R Us
**** Smith <- lol
Coles
Woolworths
Target
Drake Supermarkets
Gamestop

Bold are shops I've actually seen them for sale.
Underlined are shops I haven't seen them for sale in.

I've found different locations of the chains may or may not carry them, but every Australia Post and Woolworths I've been into has them.

IIRC different shops carry different card denominations, so it pays to look around if the shopping centre your in has a bunch of the listed retailers.