I was fortunate and found I had two extra drums in my stash of parts. These are corroded so I will sandblast them at work tomorrow. Tonight I took the drums and cleaned them up enough to put them on my mill and rotary table to "turn" the inside diameter (my lathe isn't big enough to turn drums). The inside of the drums cleaned up OK but they are at the wear limit. I anticipate needing to arc the shoes like Glen said so they fit the drums better.
Glen, I'd appreciate any additional comments and suggestions you care to offer about how to do this by hand. I have read that some people just bond the sandpaper to the drum and rub the shoes against the drums by hand. I can see that getting out of square if I am not careful. I also have a rear hub assembly (from which I took one of the two drums). I was wondering if it would be faster/better to mount the new shoes in there and use it as a fixture to hold the shoes securely while rotating the drum with sandpaper. What do you think?