Why not try a spring loaded potentiometer? Go to this site:
www.corsa-inst.com and find
http://www.corsa-inst.com/sensors/ls15.html
Then maybe a graduated LED. I'll see if I can find one of those for you.
Edit: I can't put my finger on one right now, but I'm talking about the kind of display from a tape recorder showing sound levels in a sequential light emitting diode. Electroninc engineers, help out here a little.