[turboboy]

In case you have no luck with getting original mounts it may be worth taking the metal bush out of the rubber and measuring the rubber part.

From photographs it appears to be a normal round rubber grommet with a separate oval metal insert. I am presuming you still have the damaged ones to be able to photograph one?

You could then try to locate a similar rubber grommet from a classic car parts supplier. I am sure I have seen similar generic rubber grommets in the past.