The only Indian Oxonian I can think of is Mirza Nasir Ahmad, head of Ahmadiyya Muslims, who was educated in Oxford in the 1930s, but that's significantly after your time frame.

We can also look at the famous Mohammed Abdul Karim, and Indian secretary in the service of Queen Victoria until her death in 1901. Karim was effectively given to Victoria as servant on her jubilee, with the intention of expanding her knowledge of and connection to "her" India. He was extremely successful at court, becoming one of the Queen's most favoured advisers. This made him very unpopular with the rest of Her Majesty's houshold - Karim's biographer, Sushila Anand, attributes this to the royal household not being used to having to associate with non-royal Indians, implying that had he been "the son of an Indian Maharaja" (as you put it) he would have been better received. Really this comes down the belief that rank trumps nationality, so while an Indian prince may be below an English one, he is still a prince.

Sources/further reading:

Indian Sahib: Queen Victoria's Dear Abdul, Sushila Anand, 1996 [hard to find, but I think there's a more recent biography]

Queen Victoria: Her Girlhood and Womanhood, Grace Greenwood, 2012 [this one's free for Kindle]