MK1 Cabriolet Steering Rack Bush

I'm currently restoring a MK1 Cabriolet and decided to build up the steering rack but i'm missing a plastic bush that goes in the left hand side. I've pulled one out of a scrap rack that has got a bit hot when someone cut it off so its not really useable.

Has anyone got a decent one or know where I may get one off the shelf?