Hi Ken L,

interesting topic!
A more detailed photo would be helpful.

Have a look at page 26 of the following link: https://www.dsb.de/media/PDF/Recht/S...usszeichen.pdf
All the austrian proofmarks used after 1945 are listed there.

This information might also be valuable for you: Beschussamt ("Osterreich) – Wikipedia
"Beschussamt" means proof-house. There is one located in Vienna (marked with a "2" in the eagle), the capital of Austria and one in Ferlach (marked with "1" in the eagle, Ferlach - Wikipedia).

Hope this helps.

Best regards
Fips