Hi Pete,
this keris is as well from East Java or Madura and the handle is again janggelan style but this time from wood but don't know if it is ebony, I doubt.
For cleaning your blades have for example a look here:
http://www.vikingsword.com/vb/showthread.php?t=15429
But there are other threads where it is explained and shown how a keris blade can be cleaned.
Both keris missing it's hilt rings called mendak. It should be easy for you in the Netherlands to get such mendaks for your both (or three) keris.
Regards,
Detlef