Has an NBA game ever ended 82-79?
It has. 82-79 has been a NBA final 26 times in 73,172 games. The first was Minneapolis Lakers beat Ft. Wayne Zollner Pistons on February 2, 1949; the latest was New York Knicks beat Philadelphia 76ers on March 21, 2012.
That makes 82-79 the 846th most common final score out of 3,189 that have ever occurred in NBA. One point away, 83-79 has happened 38 times and 82-80 has happened 23 times. At one point the score disappeared for 39 years, between 1956 and 1995.