The New York dealer Fergus McCaffrey, who specializes in Japanese contemporary art, sold a much larger, 10-foot-wide Shiraga abstract in red, from 1997, for $5 million. It was among 12 works sold on the first two days. “They were all sold to non-Americans,” said Mr. McCaffrey, who noted a surge of purchases from Japanese collectors after Yusaku Maezawa bought the Basquiat for $110.5 million.