Many years ago I planted a lot of seedlings from the crab "John Downie". The trees have a lot of genetic variability but some are really excellent. I wasn't thinking at all of cider when I planted them, just wanted some cheap ornamental apple trees, but I'm very glad I did it now I'm into cider making. They make really healthy vigorous trees, and some have crabs 1.5 inches diameter with very good flavour, I got 12 gallons last week off just 2 trees, really good stuff too, great flavour and high sg. Some are very bitter or sour or tiny, but overall the result was good, just had to wait 13 years.
If you can find roadside wildlings its well worth checking them out, you might find something really good.