i don't have personal experience, but they are recommended by beyond buckskin: https://www.manitobah.ca/collections/boots

i don't know entirely how applicable this is, but this post has a spreadsheet of slow fashion brands. https://gowns.tumblr.com/post/698735634148376576/slow-fashion-brands-compiled-by-rebecca

(they may not be as durable as you are looking for)

not exactly winter gear, but i'm looking for a plastic-free (materials-wise) raincoat. i would rather have animal products than any plastic.

(and, if possible, i do not want to give money to a brand that thinks shearing sheep is somehow animal cruelty)

manitobah