Nowadays, Aleph light engines are about the rarest components you can get. I'm not sure why the Shoppe doesn't make more of these....since there is HUGE demand for them....
Oh well..... if you are lucky enough to snag one, I suggest that you don't be too picky and get them despite the bin on the LED. You can easily change out the LED later to your preferred bin. To me, the whitest and brightest LED would probably be a UW0J(K) or UX0J(K) (slightly cool color temp). Although, now, I'm really taking a liking to UV0J (kind of a creamy white tint).
Good luck with your search! If you find an extra one, feel free to PM me!
WP
EDIT: not sure if you know this already, some light engines use different converters, depending on things like your cell-configuration. Do you plan on using this for 1xCR123 or 2xCR123? Things like that. There are also different drive levels......