Has a FIBA World Cup game ever ended 78-72?
It has. 78-72 has been a FIBA World Cup final 2 times in 2,041 games. The first was Greece beat Canada on July 29, 1998; the latest was Croatia beat Italy on June 28, 2018.
That makes 78-72 the 222nd most common final score out of 1,178 that have ever occurred in FIBA World Cup. One point away, 79-72 has happened 3 times and 78-73 has happened 1 times.