Try my version of KJV adapted for the Kindle (see the link below). I think it is the best available (I have purchased almost all existing ones to see if they are any good).
Please see
http://www.amazon.com/gp/product/B002TG4P8Q/
Regarding the searchability, one of my methods of navigation is what I call the Direct Verse Jump. For example, you type John.3.16 in the find window and double-click the "find" button and voila -- you are looking at John 3:16. Try it with the sample. But let the Kindle index the file first.
I also have a hyperlinked Table of Contents (books and chapters) plus if you press left or right with the joystick you can move between the books of the Bible.