This is your lucky day! It is indeed from 1927, one of the two low-slung racecars developed by Steyr. This one was driven by Josef Hansal at the Semmering race in 1928.
This picture was taken at the Steyr Works in front of the development department.
(with courtesy of Martin Pfundner for the information and the editorial office of Veterán Autó és Motor for the photograph)