Ruston Hornsby AP head gasket

I have recently purchased a Ruston Hornsby AP which i believe is 7 hp. Has no7 stamped on end of crank along with the other relevant nos.The engine has ignitor ignition.
This engine also has a head gasket problem. Can any one advise the correct head gasket material for this engine? Should it have a copper ring on the cylinder liner?
Engine had been repaired with gaskets made from reinforced exhaust gasket,hence it now has moisture in cylinder, seized ignitor, stuck valve, and broken exhaust rocker.

Hi there, I would have thought klingersil gasket material would be fine to use on both the liner joint and the on the head (I know that's what is on my 6AP). In the spare parts list I have for the AP it only lists both gaskets as 'joints' so they may have been copper or even asbestos originally.

Thank you for your reply.
There may be quality variation in klingersil type gasket. The inner and outer gaskets were both weeping, capilliary action i believe! The head was tight as i had to use a pipe on the socket bar to undo the head nuts. A fire ring on the inner gasket would solve the problem there. Asbestos sounds good, and can probably locate some!
I am not confident with commercially available gasket material that is available here at the present time.
Cheers Ian

Klingersil is one of the best modern gasket materials and it's not too thin either around 4mm thick. It's on my ihc m and works fine

Matt