Deadly Debt — J.R. Roberts

When Clint is asked by a friend to help him get out of a jam, Clint finds he's tired of taking a hand in everyone else's trouble. He tells his friend he can't help him, and moves on. When he later learns of his friend's death, he realizes he could have saved him. He returns to Bent Fork, Oregon, and takes up the chase of his friend's killers to repay his deadly debt.