This stamp was issued 28 March 1967 to commemorate the 125th anniversary of the founding of the Vienna Philharmonic Orchestra. Scott 789 includes an organ facade, a violin and laurel leaves. The facade is not clear. The Phil plays usually in the Golden Hall of the Music Academy, but that is not the facade include on this stamp. This could be the organ at the Schlosskapelle in Schoenbrunn. Here is information on that organ. I don't know if the Phil ever plays at Schoenbrunn, and if not why this facade might be on the stamp. If you can help identify this facade for certain, please contact me, so I can have the correct information here.