The Already nominated were Who's Afraid of Virginia Woolf, A Man for All Seasons, The Sand Pebbles, The Russian Are Coming..., Alfie.
"The Professionals" and "A Man and A Woman" both got director nods and were box-office hits, So both of them should probably have been nominees.
"Born Free" and "Georgy Girl" both probably should got nominated because of their precursor support and Oscar nominations.
The Last spot is a race between the critic darling "Blow-Up", the Box-Office hit "Hawaii" and "Grand Prix". Grand Prix was a popular box office hit but it earned only 3 nods in compare to "Hawaii" and it's 7 nods. So "Grand Prix" is out. I think "Hawaii" would been nominated before "Blow-Up".
A Man and A Woman
A Man for All Seasons
The Russian Are Coming, The Russians are Coming
The Sand Pebbles
Who's Afraid of Virginia Woolf?