Hello Paul,
it's a plastic fake handle, send it to me and I dispose it for you!
Seriously, I would agree with you that it will be from Lampung or surrounding area. And when it is from sperm whale tooth (what I guess) it would explain the rather big pesi hole, the natural holes from this teeth are rather big, it will has had a peg from wood or other material with a smaller bore in the hole, I've seen this by whale tooth handles or very old, worn out handle holes before.
Other as David I think that this handle has a good age, I just compare the patina with whale tooth handles from my own collection. It's a very nice handle, congrats!
Regards,
Detlef