Odd Looking Postumus Dupondius/Double Sestertius

Interesting coin, really small flan. No doubt it's unofficial.

The words that instantly came to mind were
'contemporary barbarous'.
That is what it's style and weight suggests to ME, at least.

If that IS the case, there may be no catalog reference for it, as a contemporary barbarous coin.
It's status and authenticity could depend heavily on opinion only.

I think it's genuine, not a modern fake, in line with my opinion above.

Yes sel you are quite correct about the attribution being a bit 'up in the air' so to speak.
I listed the Sear and RIC as reference for the type. Even when I first began collecting I was drawn to Postumus by his high quality artistic style.

Alas almost all these early purchases were sold off long ago
They were quite affordable too back in the early 80's.
Fortunately most of the proceeds were spent on things like Asses of Hadrian !