There were in fact a number of Cali-Masi track bikes built. They were custom order only. They were built using Columbus tubing as opposed to the Reynolds used for most of the road bikes. Mario would pretty much handle that stuff, but the other workers did some of the standard operations like filing lugs and so on. They come up for sale now and again.
I don't think they could be considered "different" from the Italian Masi track bikes other than they were built in the USA; which generally translates to somewhat higher quality workmanship and more consistent results.
La Mesa, CA
It dawned on me this morning that I can't recall seeing a Masi pista from the Carlsbad operation. Can any Masi-stas confirm if they were available Stateside as either a production or custom model? Or did Masi track bikes inherently come from the Vigorelli operation? If Cal-Masi pistas were available, how (if at all) did the models differ from those available in Italy? Any owners care to chime in or share pics?