Hi pcathcart,
Sorry for the delay in getting back to you. I was just speaking with our outerwear team about this and, unfortunately, at this time there aren't any plans to produce 4XL items. Sorry about that. Since the garments generally run a little big, would you be interested in maybe trying 3XL? I normally wear large shirts/jackets, but actually wear a medium in FJ gear so it might be the right fit for you. Let me know if I can help with anything else.
Chris