I don't know exactly what you are looking for, but my take on this issue is:
1) Traditionally, India has been the closest of partners/ allies of Buddhist Countries (Be it erstwhile Cambodia/Laos or Indo China, Burma, Thailand, Bhutan, etc.)
2) As Buddhism is an offshoot of Hinduism (almost 99 % of Hindus believe in Buddha and his teachings), we share many common heritage in terms of culture, languages, customs, etc. So, in a way, Hindus are not alien to Buddhism and its philosophies unlike to the other faiths like say Islam, Judaism, etc.
3) Thirdly, being a secular country ourselves, we have pretty good relations with almost all like minded countries, be it Isreal (Jews), Russia/ UK (Christianity), Malaysia/ UAE (Islamic), Bhutan/ Thailand (Buddhist). In fact, India has states like Sikkim, Arunachal Pradesh, etc. which are Buddhist Majority.