I found this insightful little piece in which Pizzolatto shares his dream cast on mybookthe movie.blogspot.com; this was back in 2010 when Pizzolatto sold the screen rights:
We've sold the movie option to a production company that's very enthusiastic about the work, so hopefully a movie will go forward. In my fanboy imagination, though, I suppose I'd fantasy cast something like this: Sam Peckinpah circa 1972 to direct. I of course would write the script. Starring Nick Nolte circa 1985 as Roy (I'd also take Warren Oates,'76), Natalie Portman circa 2002 as Rocky, Harvey Keitel as Sam Ptiko, Annabella Sciorra as Loraine, and, uh, Marisa Tomei as Carmen. Sure, why not.
"Obviously Roy and Rocky are the two big roles, and you need a brutish, atavistic man to play Roy, an old-school tough guy possessing range, with a voice that can be played like a box guitar. Nolte, of course, would have done outstanding work. I know Warren Oates isn't always classified as a tough-guy, but the important thing here is that he was a bad motherfucker, and there's even a line in the book where somebody basically tells Roy he resembles Warren Oates. Nowadays...? Viggo Mortensen? Liev Shreiber? Bruce Willis?
Rocky is a sprite, albeit a damaged one, so for that I think of a petite actress with a well of emotional depth. Forgetting the Star Wars movies, that'd seem to be Portman."Okay, so Schoenaerts stole the role from Willis (too old), Shreiber and Mortensen. The question remains, who would make a good Portman, circa 2002? Chloe Grace Moretz? Hailee Steinfeld? Willa Holland (Arrow). Either of the Fanning girls, Elle or Dakota. Of course, these are all the usual suspects. Ideas?
Chloe Grace Moretz as Mia in If I Stay
Willa Holland as Kaitlin Cooper in Tiger Eyes
Hailee Steinfeld as Juliet in Romeo+Juliet
Elle Fanning as Ginger in Ginger and Rosa
Dakota Fanning as Ronnie Fuller in Every Secret Thing
WHAT DO YOU THINK? Who would you cast as Rocky?