Rating it purely for scariness- and how else should you judge a ghost story?- I give it no more than 4 or 5 out of 10. "Things in a dead man's eye?" No, I don't believe in that either. The most unsettling moment comes when- having always observed Hummil from the outside- we are suddenly jolted into his shoes and see what he sees- as he sees it.
The true horror is existential. Four men gather to play cards once a week, in choking heat, in a bungalow with a torn ceiling cloth, not because they particularly like one another, but because they'd otherwise go mad from boredom and stress. If I don't rate this as one of Kipling's masterpieces it's because I feel it might have been even better- by which I mean more frightening- without the ghosts.