In 1659, the Holy Roman Emperor, Leopold I would confer on David de Büren (1614-1659) and all of his descendants the title of Baron of the Holy Roman Empire and Austrian states. The actual proclamation would not arrive until 1669, FedEx anyone? Along with the proclamation came an illustration, the emperor's seal, an orb and scepter. I have reproduced the seal and illustration below.
The illustration shows the de Büren crest in the center and the Imperial eagle above.