Jyo,
correlating the point of aluminum record/your grandfathers visit to U.S, there is a good chance this could be his own recording.
i read somewhere, during the early days, there used to be recording phonograph kiosks installed in railway station, and any one can get their voices recorder for few penny.
these discs cannot be played in any modern day T.T's.
the only option is to play it in the gramophone that too with a wooden needle and get it recorded through a microphone. playing with a normal steel gramophone needle will spoil the grooves.
i can give it a try.. but i am also on the look out for wooden needles.