The only thing you can't replace on these is the hubshell. That is fine. And the ratchet teeth also seem fine. You can push (or screw depending on the year) the left (low gear) ratchet out of the hub if you need/want to replace it. It's really nice because you don't have to rebuild the wheel.

Miraculously, I think this one only needs those gears/axle and pawl spring that nlerner posted. I still have to assess the teeth on the ring gear, which may be worn but probably will be fine.

But yes, I am regretting having cut apart the three-speed EA3 wheel from a '70s Columbia Sports (kinda lousy even when new) just a few months ago. The Raleigh rim and spokes are better quality, and the Columbia build quality is crap, but this one has seen a lot of crap. I could have swapped, one and done, and instead I'm rebuilding. I promised the bike to a good friend's boyfriend for short money, so I've got to deliver. (so they can ride together, cuuuuute )