I have them (or rather I have one pack, just sold several so need to stock up again). From memory the oart number is 36181, and it gives you one idler, one geared axle centre and one plain axle centre, so you need two packs to do a whole block.
Shipping to Oz is no problem, you even get the VAT back (VAT free about £3,33/pack), but postage is a killer - to comply with Paypal T&C's you need proof-of-delivery and that's going to be closer to £10 than £5, maybe more - depends if they'll squeeze into a 'large letter' or not.
Jonathan
g-bits