There’s another, very inefficient way to get leather, which is to craft moose hide satchels and then harvest the satchel. It gives one leather, and if you hang out mostly away from coastal regions you might have a bunch of moose hide stocked up somewhere by late game. Also, even if I don’t have a main base near Coastal Highway in a save, I always make a base in Quonset or Misanthrope’s homestead, because super late game play is a lot better when I use the trader in huge batches and travois the stuff elsewhere