Rye Berry Substitute Just To Get By?
I am planning to try pumpernickel for the first time but having a little trouble finding rye berries locally. In particular, a bread as similar in ingredients as possible to Chad Robertson's Rugbrot. Recipe here: http://abreaducation.com/blog/2012/08/chad-robertsons-rugbrot/ 
Is there a substitute for rye berries that will work close enough for what I am after? I bought some steel cut oats today. Maybe those?