AHK1N BECAUSE OF AGE* VEkalaka, Oct. 10.—(/P)—Seventeen-year-old Alva Askin, convicted here yesterday of manslaughter, will be sentenced next Tuesday morning. The jury recommended leniency because of his youth.The boy, together with his brother, Bob Askln, rodeo star, and Wesley J. Striker, was accused of having delivered fatal blows to Charles Haven, 62. The beating was administered when Haven and his son-in-law, Charles Emerson, stopped to aid them in moving their stalled automobile.Trials of Bob Askin and Striker were postponed until another term of district court.