The medical clearance is from a regular GP. I believe the training and experience of our doctors is equivalent. This letter would say you aer healthy enough to have surgery. I suppose a private therapist would work for the therapist letter. You can call or email his office, as I think there are a lot of patients from the UK who have been to him. I was there with some folks from Ireland.
BTW, would recommend staying at New Beginnings Retreat. They take care of everything for you, make sure you get to appointments, drive you all over, etc. It's probably more economical than staying at a motel.
--Jay