Dear David,
Here 2 examples from the RMV Leiden collection.
one looks like bark with leather pieces with the hair still on it.
The other one is made from a fiber with leather fixed with rattan.
As for your example. the holes in the bone scales show no wear at all and to me they look like machine drilled.
The hennep wire use to fix them would probably not hold long when this is worn. I don't think this was made to be actually worn in a tribal context.
Best regards,
Willem