Ignoramus28889 fired this volley
in :

http://igor.chudov.com/projects/Brid...ract-2-CNC-Mil
l/27-Univer-AE-1001-Four-Way-Pneumatic-Valve/

Crap! I think I see that is a "manifold" style valve, requiring a matching
baseplate or stacking manifold for use.

If you replace it with something like an Alpha-body valve, you'll have to
re-do the plumbing and mounting.

Better to look for a rebuild kit, Ig.

LLoyd