If I were him, I'd seek out the rustiest, ugliest example possible and get it mechanically sound.

I used to keep a pile of rusted parts around for anyone buying a cheap machine to use around South Beach / Miami Beach - enough so that I could build up such an ugly, rusty hulk that nobody in their right mind would steal it (or expect it to work). Coaster brake rear wheels really came in handy, for it allowed me to use the rustiest steel rims I could find without worrying about braking surfaces.

-Kurt