Buying Direct from Turtle Beach

Has anyone ever purchased directly from Turtle Beach's own website?

They've got a sale on at the moment, and their Australian website has prices listed (in AUD) as well as a 'cart', however there's no apparent way to actually add any item to your cart. The other selectable regions allow you to add to the cart, however do not ship internationally.

Here's an example:
https://intl.turtlebeach.com/au/stealth-700-ps4

Any idea on what may be causing this?

Thanks