Medical photos
The photos for medicals are like regular passport photos, front on, no requirements regarding size of face etc. You can get them done in the US or there are plenty of places in Mumbai that will give you the photos "instantly", using polaroid. I got them done in the US (cost an arm and a leg) and then I repeated them at My Own Studio (Rs.100 for set of 4). The guy at My Own Studio took them along with the side pictures and delivered them to me within 6 hours.
Bottom line, I would not be too worried about the photos for the medicals. You can get them done at your convenience. My own impression is that they are mainly for the benefit of the doctor so that they can associate a name with the face when they do the cursory medical exam.