I just looked at bikes I have hanging in the basement:
Cinelli: 42/50 with a 28 and NR rear.
Paramount: 36/42/50 NR triple with a 28 and a NR rear.
Hetchins: 36/42/50 NR triple with a 28 and a NR rear.
Getting the chain length right is all it takes, though the 50 helps.
Aldo mentioned the Legnano may have a Record. He could be right, I don't recall and I don't have the bike handy. I just pulled a Gran Sport and a Record derailler out: cage jockey wheel to jockey wheel bolt is identical, bolt line is offset from pivot point on Record vs. lined up for Gran Sport.
I'm pretty sure my Youngs, my Carlton and my Olmo have a 28 and a Gran Sports as well, but they're deep under the house.
Ted Williams