Has a FIBA World Cup game ever ended 88-84?
Exactly once. On October 3, 1978, Brazil beat Italy 88-84, and no FIBA World Cup game before or since has ended that way. When it happened it was a scorigami, the first 88-84 in league history.
That makes 88-84 the 240th most common final score out of 863 that have ever occurred in FIBA World Cup. One point away, 89-84 has happened 1 times and 88-85 has happened 3 times.