Vandoo, I have seen a few surprisingly large sperm whale teeth. Like really large - we're talking maybe 18-19 cm instead of the usual 12-13 and a proportionate increase in mass and girth to go with. They were shown to me by the Mammal Dept. curator at the Zoological Museum of Copenhagen, which holds a really large collection of cetacean material. At the time these teeth totally blew open my frame of reference for the size of these guys. The largest tooth was very old and had a rather worn down tip, so must have been even larger when alive. That whale would have had to be a leviathan for sure.
I totally agree with you that it's a possibility here and your proposed orientation is spot on - sperm whale teeth have a relatively shallow root canal and the ivory is really dense, so I think it would make the perfect sword hilt and this one certainly has the shape. Like you, I would also love to see a pommel-end shot - perhaps the canal is still evident.
Willem, this is an awesome find from the archives!! Never have seen a
sikin like it before - I hope that Charles is still enjoying it!
Cordially, - Thor