It is likely a royal gun from the Austrian Hungarian empire.
Very few of the Prince Rudolf or Franz Josef sporting weapons exist and the verbiage is purely advertising. The appointment occurred after one submitted several examples and warranted a stout yearly fee. Being supplier to a court could be from the dog handler on up. Without strict provenance with a connection the the King or Emperor's chamber, I for one would be reluctant to believe. It's akin equating a post WWI German sporting weapon to H. Göring.
Kind Regards,
Raimey
rse
