[Jacques Reed]

Hi Dave,

Thanks for that information.

I deleted the post saying it was an O-ring between the cover and the ring.
Not sure how it got into my box of shock absorbers but it ain't there no more.

Apologies to all for the red herring.

There is no great pressure in the reservoir so a good thread sealer and gasket maker such as Permatex should do the job.
Sounds like it would be almost impossible to source the original sealing material. Anyway, if more modern materials does the job why not use them.

Look forward to hearing there is no seepage on yours.

Cheers,