books for people with ridiculously narrow taste

right. my father is impossible to buy for. enough money to buy whatever he wants whenever he wants. zero hobbies. taste that can only be described as 'outrageously ascetic'. buying him baubles or clothing or anything he needs is not an option.

which leaves books. he does read. he only reads books by len deighton and john le carre. and books set in england/ireland between 1961 and 1976. books about scummy british detectives and gangsters and the like. can anyone recommend anything he might like that is widely available that he hasn't likely already read?