A piece of L.A. basketball history is hitting the auction block -- the game ball used by Kobe Bryant, Shaquille O'Neal and the Lakers when they won the 2000 NBA Finals!!
TMZ Sports has learned bidding for the item is part of the Sotheby's "Winter Sports Classic" ... with the company showcasing $30 million worth of sports memorabilia at The Breuer Building in New York.
The ball -- from Game 6 of the Lakers vs.