What would this be ?

[Rick]

I think it's safe to say that whatever this is it has been cobbled together from disparate elements.

I can't remember seeing a curved fid (Dad did a lot of splicing) in my Old Man's ditty bag.

A hone; were they often made from wood?
Maybe it's some kind of home made burnishing tool?

The hilt looks like a hilt from an Argentine Criollo.