I've been buying from Grain Process Enterprises in Scarborough. A 50lb bag of either malt barley or rye was about 15$. If you call them, they'll be able to give you more pricing info. I'm trying to source stuff that's more local, but I'm in the early stages of that!
https://wildernessreturn.files.wordpress.com/2012/04/grain-process-product-list-may-2011.pdf