If you do find some with life left in them, do not ever use semimetallic shoes -- you don't want to wear them out. If you have to turn them, tell the machinist to do the lightest possible pass.
This is just silly. Heaven forbid you actually want to use your brakes to stop your car. No thanks, I'd actually like to have my car stop when I need it to. Easier than explaining to the other driver that you couldn't stop in time because you were using horribly performing organic brake shoes so you could get your outdated drums to last longer.