Have you measured your heifer's pelvic area? I would do that before I'd consider anything but an angus CE bull. If she has sufficient space, then you could consider Simmi bulls.
Mo Better is considered a CE bull and he will throw white.
Mo Better's CE EPD is 4.4 which I think is too low for Angus heifers.
I really can't recommend any blaze face Simmi's for CE. The only one that comes to mind is Lazy H Pathfinder, but he's not proven enough by my standards for Angus heifers.
If you still want half-bloods, I would use any PROVEN Simmental bull with a 15+ CE EPD. Some that I know of are Dream On, In Dew Time, Hook's Shear Force, Dikeman's Sure Bet, and Olie. I'm sure there's more out there.