SJ, I do not know of any one book, or essay, or article, or paper that will cover what you would like to learn about. In my opinion, the only way to get close to an understanding of the keris is by in depth study of Javanese/Balinese history, society, culture, and all associated elements in these fields. I've been at this for close to 70 years, and I do not believe I will live long enough to ever complete this study.
I recently contributed a chapter to a book produced by SUNY that takes a philosophical approach to personalised objects. My chapter deals with the way in which the keris has developed from something directly connected to an Indian blade form and that in its early days was just a weapon, through to it becoming recognised by UNESCO as a part of the intangible cultural heritage of the Indonesian People --- and I guess by extension, of the entire world.
This chapter is a very superficial over-view.
The keris in Jawa is now, and has been for some time, a dominant cultural icon, this is in large part due to its inseparable association with the Gunungan, which is perhaps the oldest and most influential icon of Javanese/Balinese culture.
The keris is in fact a symbolic representation of the Gunungan, as such it relates to Mount Meru, ie, Mount Kailash, and in turn to the Old Jawa & Balinese multi roofed temple, the meru, and it relates to the Balinese cremation tower.
The idea of the keris being a temple, or shrine also can occur in Hindu culture in India where warriors regarded their swords as shrines (Elgood).
Belief systems in Jawa overlay one another, so at its root we have the old indigenous beliefs centered on animism & ancestor worship, then there is the overlay of Hindu-Buddhist belief, which in turn was overlaid by Islam. The Javanese approach to everything is not one of "instead of", it is always "as well as". So in the case of, let us say, a Javanese person becoming Christian that does not mean that he then discards the beliefs of his ancestors, rather he adds to those beliefs. If one deity is good, surely more than one is better.
Here is a link to the bibliography attached to something I wrote a few years ago, it is reasonably comprehensive, but if you recognise that there is no short cut to what you want, you will find plenty of information in the works listed in this bibliography:-
http://www.kerisattosanaji.com/inter...n-bibliography
There is definitely a close association of the Javanese/Balinese keris with the esoteric, regrettably, this association has been corrupted, and the further we move from the center of keris culture, the more corrupt this deviation from understanding becomes.