Check this thread;
http://www.fordforums.com.au/showthread.php?t=11437670
Not specific to your car, but important info.
I would contact the seller of your eBay key, as he doesn't appear to post to Oz.
If you can get this key at that price it is worth the punt.
But what will need to occur when you do get it is to find a very good locksmith and hope he can code off your original.
The price of $150 for a guaranteed key doesn't seem excessive.