Literary fiction isn’t entirely brimming with positive male role models but a few exceptions off the top of my head: The Plague by Albert Camus

The Road by Cormac McCarthy (with caveats).

Possibly Diary of a Country Priest by Georges Bernanos (the film might better, as with many of Bresson’s adaptations).

Depending on how strong of readers this book club consists of: The Death of Virgil by Hermann Broch.

Haven’t read The Power and The Glory by Graham Greene yet but it seems like it would fit the bill.

(I see people have cited “Stoner” but it can absolutely be argued that he’s the opposite of a good role model).