I am looking for ten Kimball Bakelite upper valve seats to replace ones
that broke when I tried to remove them.  They are 7/8" outside diameter
with a 24-per-inch screw thread.  They have a 7/16" hole and are about
3/16" thick.

Applying heat helped to remove most of the valve seats but these were
stuck too tight.  Any help or suggestions would be appreciated.

Don Gehrke
Phoenix, Arizona