Trying to find prices for stuff other than corn and beans

Been trying to find current prices for grains that arent corn, beans, or wheat.

So far not having a whole lotta luck.

Anyone here know where I could look for grains other that the 3 listed above?

Looking for millet, yellow peas,flax, barley, and buckwheat.

Any help is appreciated

call the local co-op--or what ever they are these days--local feed mill etc