Nigel: yes, it's a bina - more widely known as an Indian harmonium. They usually have up to five drones. The shrutti box is just drones - I think about seven on a simple one, up to thirteen on a bigger one. I did borrow Jackie Oates' one for a couple of songs on an unplanned 'fringe' concert that Rumworth Morris (with whom I was dancing) did in the lovely old Unitarian(?) chapel at Sidmouth last year. I'll probably get one one of these days!
John Kelly.