So the year must be 1954 or 1956.
According to the catalogue raisonné Cisitalia, there was no Cisitalia participating in the Mille Miglia of 1954 and 1956,
but in 1954, a Cisitalia was participating in the Targa Florio.
I do not know which one, but in 1954 the 33DF Voloradenta was made.
So my guess: 33DF TargaFlorio 1954