Has an NBA game ever ended 82-73?
It has. 82-73 has been a NBA final 20 times in 73,172 games. The first was St. Louis Bombers beat New York Knicks on March 10, 1948; the latest was Utah Jazz beat Memphis Grizzlies on December 18, 2016.
That makes 82-73 the 985th most common final score out of 3,189 that have ever occurred in NBA. One point away, 83-73 has happened 21 times and 82-74 has happened 13 times.