I am not seeing any Schreger lines which are generally found on elephant ivory. That would be a telltale with you powdered ivory and other material mixture Green that would distinguish it from the real thing. But this is most probably antler or bone. Bone will not always be porous depending upon what bone is used. It is easier to distinguish bone from antler in hand than in most photographs.
I would agree that this is a fairly contemporary hilt made anytime within the last 30-40 years. The hair/headdress of this figure seems unusual for Balinese culture so perhaps this has some Thai or Chinese influence at work.
