Googling "colloidal graphite" reveals many potential sources and
compositions including this one in isopropanol:

http://www.macbicnj.com/glsblwequip/18821.htm  or this one
http://www.ebsstore.com/control/product/~category_id=G3/~product_id=P-CG-45;jsessionid=hvdyjb9ru
depending if you want aerosol or liquid.

The stuff seems to have a very wide range of uses from making
conductive surfaces, electron microscopy, making a resist for
soldering,  to use as a mould release agent.  (I figured the 200
liter packaging was probably excessive for piano/organ work.)

Google also turns up some history about its inventor, Edward Acheson,
who also invented the synthetic abrasive carborundum:
http://chem.ch.huji.ac.il/~eugeniik/history/acheson.html or
http://web.mit.edu/invent/iow/acheson.html

Cheers,
Roger Wiegand
Wayland, Massachusetts, USA