I know Bayside is union made in the USA and has some pretty big sizes, up to at least 4x, maybe 5x or 6x. They're a bit limited as far as color selection, but other than that I love them. There's also Windjammer out of Pennsylvania, they have a greater color selection than Bayside but I think they only go up to 4x. Both brands tend to run a little bigger and thicker than AA but are still very comfortable and durable.
For my T-shirt line I only use sweatshop free, made in the USA brands, so this is important to me.
I am very impressed with Lifewear.net. American-grown, American-sewn, and also union and family owned. It's so good. And the shirts are so smooth, vibrantly colored, and sturdy. Order 100+ mix/match of colors and sizes, and you get a discount. I like the idea of really knowing the people behind the 'union label', vs. Bayside that is so anonymous. Lifewear tells you which local their employees belong to.
Oh, and their sizes are "generously cut" and, while it's a good idea to call ahead about sizes in stock, they range from XS to 4XL. "Generous cut" basically boils down to this: their XS is a typical imported S, all the way up.
After that, Royal Apparel is mostly made in USA (some in Mexico), and does not have the skank/stank of American Apparel. Have not yet had the opportunity to order with them, but they do have 100% organic made in America.
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