Dan,

Either an OEM, or we ran a Harvest Services concave (Craik, SK) in a 9500. Concave is compatible with the OEM beater. Line bored to a perfect circle and would run circles around the original '00 series concaves (especially in wheat), not as much as the new '10 (and later) concaves.
Built much heavier, lot less flex, and we ran ~3 seasons, and then sent it back to the plant to be re-bored for $200, restoring it to pretty much original performance...

Argis is the Ontario distributor.

George is pretty proud of his stuff, but I will confess we run his filler plates so that we have better performance in wheat and beans without pulling out the OEM's.

Luke