Where Do You Get Your Seeds?

I am *loving* our new juicer (Omega 8003) and so are my kids (it's our new homeschool Science project-lol), and so am wanting to start growing wheat and barley grasses for juicing.

I have wheat berries that I use in grain grinding for flour. Can I grow those, or do I need to have a special type of wheat seed?

Same with barley--do I need unhulled seeds?

Also, are some wheat and barley varieties better than others for growing grass, or does it not really matter?

Thanks much!
Warmly,
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