Cardox Unit

Cardox 4 ton
M323W
D41320-2

Does anyone know what brand of compressor Cardox used on their units?
Our local fire extinguisher company has a unit with a leaking shaft seal.
It is a ***** unit, belt driven 1.5 hp motor. Piston machine, similar to a old Frick Blu Cold.
I tried to call Chemtron/Cardox but because of the holidays I haven't received a call back.
The owner was told that the entire refrigation system of the tank needs to be replaced, we are trying to repair it so he can budget the money to do that.

Is anyone familar with these units?