This 12 digit calcluator has a normal price of $23.99. Features include a big tiltable display, 3 key memory, tax and markup functions, dual power, and it's nice and large at about 20cm x 14cm.
Spotted in-store at Officeworks but I guess you could also try ordering it online. Stock would vary from store to store and may be quite limited though.
Update: Brisbane CBD store has about 50 of them out front in a big bargain bin.
I tried ordering it online - sold out :( I might try in store next time, good deal!