GEARBOX SWAY DAMPER question

[GreasyJoe]

Hi
I had my SE turbo inspected at a Lotus garage and provided me with a list of things I need to work on or get someone to work on. Basically anything that's made of rubber were the main items.
One thing mentioned was the gearbox sway damper (only one? still newbie).
Anyone know where to get a replacement, or carry out maintenance on this item. Only seen one on e-bay starting at £20, and even that said it wasn't in good nick. No details of the problem but I'm guessing the rubber gaiter at the end of the piston is a bit perished?
Get the bicycle repair kit out?
In addition where is it? Access underneath?