You'll have to check the shipping for yourself
There are places that will ship internationally but often they will use someone like UPS, as does Zesco. Out of curiosity, I went to the UPS website and got a quote to ship a 1-lb. package (which I would wrap myself and deliver to a UPS retail shipping store), with a shipping weight of about 1-lb. (a 16" pizza screen weighs about 6 ounces), to a residence in Sydney, Australia (I picked the city out of the air). For purposes of the quote, I would ship from where I live just outside of Dallas, Texas. The three quotes that were given ranged from $81.72 to $133.36.
I was once told by a company that the best way to handle international shipment of small items like what we are talking about here is to have the item delivered to an address in the U.S. and have the recipient mail the item to the foreign destination, which would be far cheaper than using a carrier service. From what I can tell, the seller on eBay would be such a recipient and most likely would be using the mails to ship the screen to ninya in Australia should she decide to purchase the item. It's not terribly likely that ninya will be able to get a much better price since the bulk of the total cost is shipping, which is likely to be about the same no matter who the seller is. For example, for U.S. Postal Service shipping for a 1-lb. package via Express Mail to Australia would be about $25-$27 based on a quick check at the USPS website.