Hi Jor-el, welcome to the forum.
You should try to find :
De Kris 1-2-3 - Magic Relic of Old Indonesia
(by G.J.F.J. Tammens)
These three volumes are written in Dutch and English and contain a lot of information and also a multitude of pictures and drawings. Not cheap, but worth their price.
Here is a link where you can still buy them :
http://cgi.ethnographicartbooks.com/...=3726536.26103
This museum book shop also has other good keris books.