In the Cremona air chest, the valve stem screws into the pouch,
which is reinforced on both side with a stiff .020" thick material
glued to the pouch.  In the past I have always salvaged and reused
this material, but in the present case it was badly mangled during
the prior rebuild and must be replaced.

An assortment of sheet plastic of the correct thickness is available,
but none glues well to leather with hide glue.  What is the currently
available material for use in this application?

Thanks for your help,

Scotty Greene - DeBence Museum