No one's sure of the count on the bodies. One for each pop might be cool but could end up really cluttered. Hard to say.
I would think the skull/spine would be considered one "toy".
That leaves the lock claw and of course the mysterious 'fourth'. I had been holding out hope for an actual chopper over the jungle hole, but the reveal of the skull curtailed that. Your guess is as good as anyone's at this point.