Lichen Goods
About as far from an industrial sock as it gets: 100% British wool from small UK farms, worsted-spun into a 4-ply yarn in Yorkshire, then knit by hand on a manual machine that needs no electricity. There is no synthetic elastic - the stretch comes from the yarn and a ribbed construction - and the packaging follows the same rule, an organic cotton bag inside a handmade recycled-paper sleeve. Each pair takes roughly four hours to make, which is both the reason it's plastic-free down to the sleeve and the reason stock is intermittent.
How clear are their specs?
Names the breed (Bluefaced Leicester), the ply, where the yarn is spun, and states plainly that no elastic or synthetic fiber is used and that the wool is unbleached, undyed, and mulesing-free.