Has a FIBA World Cup game ever ended 51-48?
Exactly once. On January 21, 1959, Uruguay beat Argentina 51-48, and no FIBA World Cup game before or since has ended that way. When it happened it was a scorigami, the first 51-48 in league history.
That makes 51-48 the 240th most common final score out of 863 that have ever occurred in FIBA World Cup. One point away, 52-48 has happened 1 times and 51-49 has happened never.