Endoscopic sympathectomy is probably best done at Sir Ganga Ram Hospital in North India, at Gem Hospital in Coimbatore, and perhaps one or two centres in Mumbai.
I do not know how advanced it is. Please ask your prospective surgeon. However, open sympathectomy is advanced, and is not very invasive. All major institutions in India would be doing open sympathectomy. A chest surgeon or a neurosurgeon may be better than a general surgeon for this. The cost would be about 30-40,000 in most institutions for either open or endoscopic sympathectomy.