Bugis Celebes Keris / info on age/dapur ?

[asomotif]

Recently bought this Bugis Keris from a pre WW2 collection.
So before WW2 is sure, but can you help me on the age of the blade ?

The hilt seems Hippo ivory to me, am I right ?

There is a simple loop of wire attached to scabbard. seems of later date.
Any suggestions how such a loop should be fixed ?

Thanks for any input.
best regards,
Willem