Dear Henri,
According to the
Isegrim entry I provided, a total of five coins of your
type were supposedly identified, including the piece in
Harvard (COLL
HARVARD 29[2]). Another of the five is in the
BnF, but I was unable to find it yet in their online database ("
SNG FRANCE 2 2121" is actually a coin of
Herennia Etruscilla!)
In any event, I would rate your coin at least uncommon, possibly
rare.
Best regards,
Mark Fox
Michigan