Reddit reviews Play the Harmonica Well

Two possibilities for instructional material include Jim Hughes' book, wich starts with the very basics of both harmonica and music reading, and Douglas Tate's book, brief and subtle but containing excellent advice.

From the other comments, though, there appears to be some confusion as to whether you simply want sheet music (and already have enough harmonica technique to tackle classical music) or whether you also need to learn to play the chromatic well enough to approach this repertoire. Perhaps you could clarify a little.

By the way, another discussion group that focuses entirely on the chromatic harmonica is Slidemeister, and it might be worthwhile to inquire there, as well.