@ixtab
You don't need to download a KF8 book. Simply download and install "Kindle Previewer" from Amazon (it's free) and open any ePub. The previewer will build a mobi file containing both the mobi8 and mobi6 versions. It will be then opened in the previewer where you'll be able to simulate the various kindle devices: Kindle Fire, Kindle 4, DX, Kindle for iPhone and for iPad. There's not a specific entry for Kindle Touch, but - apart from screen size and colour - it renders KF8 like the fire.
I made this
Galileo Galilei book (copyright free) this way.
Otherwise you can download an Amazon KF8 sample from
this post. It's just a sample, but an interesting one, with embedded fonts (actualy a subsetted one).
I don't know where your code is intended to interact with the kinlde process queue. By the way, if you could add your code where HTML gets parsed, instead of where it gets rendered, you would simply need to add some
­ on the fly, and let the rendering engine of the kindle do the rest.
On the other hand - as you say - it would work only for KF8 books...