Arjan,
The German blade smith also confirmed that he uses the ribs for his hilts (see above) so I assume those, and the more expensive tusks, are the parts to use for hilts.
On the wikipedia page you quoted it also says that the tusks are used for sword handles in the Gulf states.
All over the archipelago you will find keris hilts made from dugong, gading laut, but I am not sure if it's only the tusks or some other parts [ribs] are use for this too? So maybe "in parts of Indonesia they [Dugong] are considered reincarnations of women" isn't such a bad thing anyway?
The full wikipedia quote for Philippines is: "In the Philippines dugongs are thought to bring bad luck, and parts of them are used to ward against evil spirits." This also seems useful for a sword or knife hilt...
Michael
PS If you do a search for "dugong" on this forum you will see several reference pictures of dugong hilts.
Here is an interesting dugong related thread
http://www.vikingsword.com/vb/showth...ghlight=dugong