This was revealed today on Isaac Adamson’s website:

Sony has acquired the Isaac Adamson novel “Tokyo Suckerpunch” to adapt into a feature Tobey Maguire will topline.
Studio has hired Ed Solomon to write the pic, to be produced by Maguire through Maguire Entertainment and Douglas Wick and Lucy Fisher via their Columbia-based Red Wagon banner.

Tobey Maquire is an interesting choice for Billy Chaka. I just do not know if he has enough “bad ass-ness” or “attitude”. I saw a John Cusack type playing him. I read this some time ago and you can get my impression from my review.