spectacular carving for comment

[David]

Originally Posted by Sajen

Don't forget the mendak!

Nope, i won't forget that. The hilt and the mendak seem to both be lovely examples of well made and traditionally acceptable keris furniture.
As for the correct name of the beastie(s) on this keris Marius, you may find yourself "fighting" for a long time to come up with a correct name. This is all the makers fantasy for the most part, taking pieces of cultural mythologies and stitching them together for his own personal effect. It is the kind of thing that may have been done to attract Western buyers who may not no better, but as Alan has already pointed out, no self-respecting Javanese would be caught dead wearing such a blade, no matter how well done the carvings might be.
It is simply not possible to obtain any reasonable understanding of the keris without also studying the Indonesian cultures which spawned it.