Shock Mounting bushes for Montego

[fbm777]

I had a problem with one of my rear shocks, became detached from the body, came apart, and basically swivelled into the road, with a loud bang. I thought that was the end of my car, but a good AA man fixed in temporarily for me. Anyway, the result is that I am now missing the lower mounting bush (sits atop the spring seat), but no one seems to make them any more, and they are quite a large size. I wondered if anyone knows where you can get an equivalent part from? Thanks.