I have an absolutely incredible set of moose hide trigger mits by Hides In Hand - a traditional leather crafter in Canada who use locally sourced hides.
I backcountry ski a lot and DESTROY gear. My hides in hand mits are the most durable and comfortable mits I've ever had. The issue is the acrylic fleece liners - I blow through them.
So I decided to make a set of sheepskin liners. I went to Bill Worb Furs - who source pelts from traditional hunters and trappers (read: mostly, but not all indigenous) and scored some hides.
I deconstructed the original liners, made a pattern and made these new liners. Cost me $30CAD and I have material for a couple more.
Totally pointless, could have bought replacements, but it was a super fun project for someone who has never made something like this before.
Better than I could probably do on my first try. And now you did it yourself. That's worth more than whatever time or money you would've saved by simply buying replacements. I feel more strongly every day that self-reliance is how we take back our humanity from the increasingly consumerist culture we find ourselves living in in developed countries.