Hi Mike, Welcome to the Forums.
I too am working on a Royal Guard, however mine will be from Return of the Jedi. My first peice of advice would be to join the ForePike.net forums. That is the home of the Sovereign Protectors Detachment. They have lots of information on all of the varieties of guards, Red, Blue, Black, Crimson Empire (Kir Kanos). I took a look and there are some great treads on who have build Kir Kanos guards. The 501st CRLs do not yet have a stardard in place for Kir Kanos. The ForcePike forums do have a section where they are trying to develop the costume standards. I would ask on there what type of guard you could start with and later develop into Kir Kanos (I'm not sure which version he belongs to I.E. episode 2, 3 or 6 etc.). There also may be some people selling Armor kits for Kir Kanos on those forums.
Good luck with your build.
Josh Mc