Armstrong Siddeley Cheetah 17 Restoration

I have commenced the restoration of a Cheetah 17 engine with the aim of returning it to ground running static state.
The engine is the port engine from Avro Anson C19 G-AGPG. I was fortunate to obtain the complete engine, engine bearer, engine cowls and the auxiliaries and prop.

However I am short of three items these are:-
The exhaust assembly. From the manuals, I have read, I believe the exhausts to be specific to the port and starboard engine. I think this is only because of the position of the take-off to outside the engine cowl. Since this exhibit will be ground based It is possible a starboard unit would do. I don’t think the exhaust is specific to a Cheetah mark number, so I think any mark number would fit the 17.
The propeller Governor/ constant speed unit type GRF/51.
The adaptor to fit the above Governor to the engine.

The pitch control cylinder internal surface for the Rotol prop is also internally corroded. Although it could be refurbished I would prefer to replace it if I can source a better unit.
Any help and advice in sourcing these items would be greatly appreciate.