TLDR; New models from the UK to Australia for ~60% of AuS GW RRP even after postage. I thought this might help anyone deciding on making a large purchase from the UK to Australia, or UK to another country where GW prices are extremely high. A friend and I just went through the process of buying a bulk purchase of new in box models from a UK GW Retailer. I had previous bought some locally used models from Sydney and some new in sprue models from he UK. However, there were some models we couldn't get our hands on (new). I was also over cleaning paint of used models and being short on spare bits to magnetise my models with all options. 12kg of models in a box with dimensions 50x50x50! £125 GBP to post from London to Sydney is the cost of a small army in itself. >< ... 80% of this box is filled with Skaven Vermin, 20% is Seraphon holding strong! All up I am happy with the final cost and can't wait for them to arrive! If you want new in box where you can take the time to pick and choose what you want and not have to sit on Facebook/Ebay and snipe a great deal and possibly end up with extra models you don't need then consider bulk from an overseas retailer with some mates.
I used to order all my models from the UK webstore when GW still let you choose which store to buy from. Easily saved 50-60% on AU prices. Now that I have a local GW that's worth supporting I tend to buy from there unless it's something I consider to be monstrously overpriced (Magnus, Archaon, and Lord of Change are freaking atrocious! I also saved a lot of money on my Seraphon/Lizardmen army buying from a place called Chaosorc Superstore (based in the US). Not quite as cheap for models as places in the UK but for the most part their postage was reasonable. I seriously considered buying a realm of battle board from them because even with a $200 postage cost it was still $50 cheaper than buying it from GW direct. Didn't buy it, but was a six pack of beers on a lonely night away from it...
Whenever I sell an army on Ebay it has always been bought by someone form Australia, USA or China everyone of them has said it is still cheaper buying from Ebay and paying the postage than buying in their own country.
That's crazy... I do miss Australia, but I would miss having proper fast internet you didn't need to remortgage your house to afford and buying minis all the time more...