LOVE THE IDEA!!
I was looking for some jet black obsidian 1911 grips for my recent tuxedo gun project but could not find what I was looking for in my searches.
I ran into some of the same comments as you indicated; IE they will crack or could be destroyed with recoil.
I don't know what you COULD charge for them, but I know if I came across the right grips for that gun, I would have gone $75-$100 to finalize it if they looked like what I wanted. Then again, I have a penchant for going overboard with my builds.
Looks awesome though. PLEASE post pics as you go along and what they look like when finished. Those would look sexy AS HELL on an all black 1911 with green Tritium Night sights and a grip side, 1/4 away shot!! That would be a magazine cover caliber shot.