From the Dodge Dart website.
Figures are rounded to the nearest 100.

1967
Dart Six 50,900
Dart V8 2,200
Dart 270 Six 49,700
Dart 270 V8 13,500
Dart GT Six 16,600
Dart GT V8 21,600

1968
Dart Six 56,900
Dart V8 3,400
Dart 270 Six 55,200
Dart 270 V8 21,300
Dart GT Six 10,900
Dart GT/GTS V8 24,100

1969 Dart
Six 61,800
Dart V8 24,600
Dart Swinger 20,000
Dart Custom Six 41,600
Dart Custom V8 22,100
Dart GT Six 5,600
Dart GT V8 15,300
Dart GTS V8 6,700