Has a FIBA World Cup game ever ended 43-40?
Exactly once. On November 3, 1950, Egypt beat Chile 43-40, and no FIBA World Cup game before or since has ended that way. When it happened it was a scorigami, the first 43-40 in league history.
That makes 43-40 the 240th most common final score out of 863 that have ever occurred in FIBA World Cup. One point away, 44-40 has happened never and 43-41 has happened never.