By popular demand from http://www.ozbargain.com.au/node/20906 :) …
These are the squash balls in question: http://www.amazon.co.uk/gp/product/B002O3DD32 and they’re currently on clearance at the local Kmart here in Townsville. In all liklihood, this may apply to the rest of everywhere else, providing that your local store has stock etc etc.
This is a very much ‘try-and-see’ deal as I just stumbled across these.
From the package/Amazon.co.uk: DUNLOP MAX BALL: Ideal for beginner players to develop correct technique with an easy to use ball that is 12% larger than the standard size and has a 40% longer hang-time compared to the Pro ball.
So, they're for beginners and they mightn't suit all the squash players out there. Still, I've got some use for it and I can't complain for a dollar (and 1 cent).
EDIT: Ignore the circle in the receipt image. Same receipt from my other recent deal and I over-wrote my original photo.
Probably won't work at other Kmarts. P1 and the price 1.01 indicate the item was marked down for being 'soiled and damaged', though try your luck and see what you find.