http://www.sunrisefarm.net/soyfreelayerfeed.html
http://www.sunrisefarm.net/feedprices.html
^--sunrise farms located in VA
http://www.scratchandpeck.com/product-category/organic-chicken-feed/layers/
^--scratch and peck feed located in the western half of the U.S...
%16 protein BOSS=Black Oil Sunflower Seeds
as for the non GMO it is possible to buy nonGMO feed it just takes a bit of extra looking, without the protein from a higher protein feed, your chickens are only getting less than %10 protein.
keep them on a constant layer feed your personal choice but make sure it is at least %16
then you could mix in some scratch
add some BOSS
and that is my mix but start feeding constant layer pellets, crumbles, or mash
the others are mainly just used as treats