Why not just order it at AT&T or apple and then it comes, you'll have it.
No muss no fuss. Of course its not instant gratification but you'll not be bouncing off the walls trying to find one.
I'm leaving the country tomorrow for ~5months 😉 I could have it shipped to someone in the US to ship to me in Australia... but at the point I may as well just buy it unlocked in Australia and not have to deal with the hassle!