Posting this here as this is a stupid way of making a "recovery", but its something. I ran the Chromecast Recovery image through koush's CWM recovery builder, and this is what came out. Haven't personally tested it due to time, but it removed a good bit of data, I'm guessing it won't work. You're welcome to try though.
Bulder Recovery
Original Recovery
Code:
#include <std/disclaimer.h>
/*
* I am not responsible for bricked devices, dead TVs, thermonuclear
* war, or the current economic crisis caused by you following these
* directions. YOU are choosing to make these modifications, and
* if you point your finger at me for messing up your device, I will
* laugh at you and give you a fluffy pony.
*/
Original Recovery