Has an Olympic Basketball (Men) game ever ended 76-66?
Exactly once. On July 29, 1992, Brazil beat Angola 76-66, and no Olympic Basketball (Men) game before or since has ended that way. When it happened it was a scorigami, the first 76-66 in league history.
That makes 76-66 the 126th most common final score out of 698 that have ever occurred in Olympic Basketball (Men). One point away, 77-66 has happened never and 76-67 has happened 3 times.