Now I'm speculating, but Pininfarina adopted that treatment of the rear pillar on the side of the car with the belt line making a curve just like this car since 1955, with a Ferrari 345 America, then in 1956 with a Jaguar MK VII etc but after the Flaminia Florida of 1957, these features are combined with small rear fins, like in the Flaminia Coupe of 1958 and laters models, but I can't find all these elements in the same car at the same time.
In addition to that, I'm sure if someone has got a Pininifarina car to sell in an Italian magazine, the name of the coachbuilder will be mentioned and underlined.