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Consider using a piezo disc, it is probably what makes the sound in the first instance. They work quite well as narrow bandwidth microphones and will produce many mV into a high impedance.  They are cheap and often sold as drum beat sensors as they can be glued to the sides of drums an the output used as a trigger for other music instruments or as a pad to be directly hit by a drum stick. Cost (imported from you know where) is about UK 20p each.

Brian.