A pre-order listing for the Xbox One Slim Kinect adapter lists the peripheral at $40 USD.
Amazon listed the accessory earlier today.
The Xbox One Slim is expected in August, and comes complete with a smaller form factor. Though the unit’s power brick will now be housed in the console itself, there wasn’t enough room for a dedicated Kinect port.
You can read more about the Xbox One Slim here. We’re attempting to confirm Australian pricing now.