Right, the Visconti-Sforza is the oldest nearly complete one. It's also the earliest one we know of that assumes that familiar 78-card configuration all of us know and love. Only four cards are missing: the Devil, the Tower, Three Swords, and Page of Coins. Lo Scarabeo's 1997 gold edition (available: US Games or on this site) was done by A.A. Atanassov, who copied the Devil and Tower cards he used for replacements from another 15th-century deck. So this would certainly be your earliest and most genuine "golden oldie."
The Cary-Yale pack is also a Visconti deck, and both Kaplan and Michael Dummett have expressed the opinion that it's probably older than the Visconti-Sforza. 1441 And 1450 have been offered as hypothetical respective dates. However, there are problems with the Cary Yale; it appears to have been an 86-card deck (six court cards in each suit including a female page and a female knight), but we can't tell for sure because some of the extant trumps are unfamiliar (Faith, Hope, and Charity). Also, only 67 cards remain, so at least 19 are missing. There is a commercial version available (also through U.S. Games, I think) for which Luigi Scapini did the 19 replacement cards. However, anyone using this deck should be aware that it is at least in part an artist's reconstruction, and not the original article. Some experts think this one was an experimental prototype, and that the Visconti-Sforza is the first pack we can look at and say for sure, "Yeah, that's a real tarot."
C. Boxer
P.S. Liliana: Very funny. People who are serious when they say that sort of thing give me shingles.