Yeah, the Viennese Forend latch(C. Harvey Patent of 1866/Rigby-Charles Harvey, an employee with Wilkinson & Son of 27 Pall Mall, London in patent no.1793 of 7 July 1866) is a 1st clue and then the Boehler tube steel w/ Imperial Eagles point to it being a Austrian Platform.

Hochachtungsvoll,

Raimey
rse