Richard Burton was 42 in Where Eagles Dare when he played the character 'Maj. Jonathan Smith, MC'.
That was over 55 years ago in 1968.
In 1984 he died aged just 58, starring in 89 films in his career, 42 of those after Where Eagles Dare was first released. If he were alive today he would be 98.
In Where Eagles Dare, I think Richard Burton looks: