The trains you are referring to are the Pullman Standard Comet 1 cars. They were pushed and pulled by GE U34CH locomotives. They were the first commercially built push pull trains. They were not in existence until 1970. They saw use into the 90's.
The CNJ had home built push pull trains they built using older heavyweight coaches. The cab cars were normal coaches with a cab installed on one end.
Atlas makes Comet II coaches and cab cars. They are slightly different from Comet Is in appearance.