David Stein, 81, former MCA executive and brother of Jules Stein, died July 31 on the island of Ibiza, Spain.Cause of death was not reported. Stein graduated from the U. of Chicago and the London School of Economics, financing his education in both cities by playing saxophone and piano in various dance orchestras. He was an agent for MCA prior to World War II. After serving in the Navy, he rejoined MCA in the Beverly Hills headquarters. In 1949, he moved to Paris to establish the French offices of MCA. He remained there until the agency dissolved. Survived by a sister.