I have plaster casts of all three of the Vienna specimens of your As, and agree that their three examples and yours all share the same obv. die. My plaster casts were taken from these three Vienna spec. and three others, total six. Looking more closely at their reverses, I find not just two rev. dies as I stated above, but rather four rev. dies. I think your rev. die matches that of the Vienna coin that is #15902 according to my notes, but it would be nice if you could confirm this with your coin in hand, assuming Vienna has posted photos of the reverses of their coins too. I only see the three obverses, but maybe I'm not clicking the right button.