There is no evidence to suggest that Ray Shoesmith is based on a real person, including "Student".
The character of Ray Shoesmith, played by Tom Wilkinson, is a fictional creation for the film. The character is a complex and morally ambiguous figure, but there is no known real-life inspiration for him.
The term "Student" is a nickname for an unidentified and mysterious figure in the London underworld who was active in the 1960s and 1970s. There is much speculation about who this person might have been, but their identity remains a mystery.
It is possible that the filmmakers were aware of the "Student" figure and may have drawn some inspiration from the general atmosphere of London's underworld during that period. However, there is no evidence to suggest that Ray Shoesmith is a direct portrayal of any particular individual.