Covelle information required

[Rossi25rc]

A recent purchase of a 1256 hc engine that has had some work done.
It has a stainless Covelle inlet manifold on.
There is a brief list of the work carried out with a rough engineering cost.
Hoping someone has any information on the name.
I will be looking to assemble the engine very soon so may need some help and questions answered.
I would also like to know if anyone has a full nut and bolt list for the 1256.

Many thanks
Ross