Update: I just got off the phone with Fishers Feed and Mill in Bristow, OK, just 21 miles from Bixby, OK, which is essentially South Tulsa. They sell to the public by the 50lb bag for grower and layer feed, and the prices are $10 to $15.
They'll do custom blends for 1,000 lb minimum, but we Okies could go together as a co-op to buy a large amount. Across the street they have their own thousands of laying hens, which makes me sad, but if anybody likes to rescue those poor battery cage layers that's a good place to check.
From the Bixby/Mounds/Liberty Mounds/Hectorville area, you take the 16 towards Beggs, pass through Slick, and look for a big white house with a Fisher sign, then follow the signs.