Oh, believe me, I have checked eBay! Sadly, most sellers don't ship to Australia, and those that do charge the same amount of postage for the large squishies as the actual Squishables website. However, I have found websites that have cheaper postage for the mini squishes - that's how I managed to get my Mythical Fire Chicken.
www.neatoshop.com
Limited selection, but shipping costs are better...