I don't know if they have harp, the only time I saw them Adam was taking that role, but the Robert Ross band is a great blues band. I'm on their mailing list. I keep waiting for them to play some gigs farther up the Hudson. It looks like they are playing in Brooklyn that weekend.
http://www.robertrossband.com/gigcalendar
Like I said, I saw them when Adam played a gig with them and they rocked (so did Adam.)
