The Man in the Black Suit(TMITBS) was adapted into a Dollar Baby back in 2003 directed by Nicholas Mariani. I think you have seen the trailer from this one on youtube.
You can ask why TMITBS is no longer available for adaption.
If the film is finished you could send it to festivals. In the...
The story "The Man in the Black Suit" is not available.
The "Dollar Baby Request" on StephenKingShortMovies.com works, the requests will be forward to King's assistent. They will reply your e-mail with information where you asked for.