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Buogiorno Don Peppino,
La leva sinistra in your photo is a Fratelli Pietra (Universal) product and is item nr. 306.
It is relatively late as the pivot screw, part nr. 359, exhibits a silver finish. Up until about 1967-68 the 306 came through with a brass pivot screw.
Usage tip - the pivot screws on these often work loose with use/time. Suggest removal of screw and adding a drop of thread setting compound such as Loctite.
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