Questions about the Tobii Glasses 2 should be directed to the Tobii Eye Tracking Research sales team.
What I can say is that there are API’s developed, distributed and supported by Tobii Eye Tracking Research. How far away things can be tracked depends on the size of the objects and how precisely the eye-gaze vectors of the individual eyes can be mapped to be directed towards the particular objects. That would typically require some sort of image analysis of the HD video captured of the outward pointing camera of the Tobii Glasses 2. How much of the scene view that is captured by the scene camera is illustrated on the Tobii Glasses 2 product page