Al Pacino was cast to star as Joe Paterno in “Scarface” director Brian De Palma’s film about the Penn State sex scandal, “Happy Valley” — but HBO reportedly has put the project on hold over budgetary issues.

In the meantime, we hear Pacino and De Palma have a copy of Amir Bar-Lev’s current documentary on the subject, also called “Happy Valley.”

“Al and De Palma are watching the film to do research on the characters,” said a source at a MoMA screening of the doc hosted by Bob Costas and Oscar winner Barbara Kopple.