A new (for me) sesterce of Postumus

Hello!
Today I have purchased this sesterce of Postumus:


The seller give me this reference: https://www.cgb.fr/postume-sesterce-sup,brm_253321,a.html
It seems to be another specimen from the same scalptor and also from the same dies.
It's really so rare or do you know others examples?

a collage in order to search dies link... i think that is is.

But I don't understand the reason why cgb said that is unpublished...

I found these two pieces:



Bastien 66 and I think that it's the same type and also the same obverse dies!