Last years commencals came out around $10,000 as a complete, so i would suggest that as a ball park figure.
The tr450, from what i hear is still in testing and may take a while to come out, maybe not something to hold your breath on.
The other bikes i would suggest thats a high end complete like this is the 951 complete that is rumoured to be coming out soon, there is a thead on mtbr is your interested, apparently not to pricey either (though thats america, over here there would be more added costs). The Trek session 88 is a really nice bike at that price range as well.
If you live in Sydney and your looking at spending that much money maybe try and get down the the bike shed mortdale, they do great builds are great prices (there blog has a top of the line yeti 303 for $9,000)