I don't have many butchers within 30 miles, and their selection is almost always a subset of what I can get at the larger grocers.
But unlike a supermarket, you can just ask a local butcher to save you some of whatever off-cut the next time they're trimming it. Normally they'd just throw it away.
That might be possible in some supermarkets.
Yeah, I was going to say, it's worth asking.