Place beans in a large saucepan; cover with water 3 inches above beans. Cover and bring to a boil; reduce heat, and simmer 2 1/2 hours or until beans are tender. Drain beans, reserving 1 cup cooking liquid. Set liquid aside. Transfer beans to a serving dish; keep warm.
Cook sausage in a large skillet until browned. Remove sausage, and cut each link into thirds; set aside. Reserve 1/4 cup drippings in skillet.
Add flour to drippings; stir until smooth. Cook 1 minute, stirring constantly. Gradually add milk and reserved liquid; cook over medium heat, stirring constantly, until thickened and bubbly. Add pimiento and salt.
Pour sauce over beans. Garnish with sausage and parsley.