A good source for cork gasket material is Organ Supply Industries
in Erie, PA.  In their online catalog look under "cork packing".
http://www.organsupply.com/

They stock sheet cork in the 1/32" thickness as well as other sizes.
It is their stock number 6000.01 and comes in sheets 28" X 50".

Ordinarily I do not use cork for gaskets, but this material is superior
to that sold by PPCo in that it is pure cork, with no other additives.
I was forced to use it in a Bush & Lane player action.  See the MMD
Archives 1999.05.14.08, "Bush & Lane Player Action With Metal Valve
Blocks".  There are also two pictures in the Pictures section of the
player action.

This is the double hernia model that is all die cast metal.  The
original gaskets were 1/32" cork and it seemed prudent to replace the
original ones with material from Organ Supply.  It worked great.

I had steel rule dies made to punch the complex gaskets and when
I finished the job and vowed never to do another Bush & Lane action,
I sold the dies to someone in the MMD whose name I cannot remember.
Fortunately all the die cast parts were in good condition and came
apart easily.

Ed Gaida
egaida@txdirect.net