[ Ref. 180301 MMDigest
 [ http://www.mmdigest.com/Attachments/18/03/01/180301_131054_thumbnail2.jpg
 

That sure looks like the unit valve used in Stinson band organs.
We bought a set a couple of years ago when we were reworking the
Stinson organ at Griffith Park.  As I recall we bought the valves
from Alan Stafford.  Also, check with Terry Haughawout as he has
assumed Don Stinson's service work.

Bruce R. Pier