Are you Gerry Harvey by any chance
because if postage costs were anything like your example eBay would have shut up shop in Australia long ago. Standard postage costs for a DVD (I just checked) - about $5. Lenses (I know from experience) - around $10-$12. I can't imagine where the $50 comes from - are you paying someone to ride shotgun? Your 10cm cube shipped from Brisbane to Perth, assuming the maximum weight of 20kg (what are you shipping - solid gold?) - $64.95 for standard shipping. Yes, you can pay a silly $200 plus for express shipping but that's utterly irrelevant to point of the article. For something more realistic - under $10.
Nice try Gerry, but remember - the internet makes it ridiculously easy for people to find out when they're being ripped off.