Rear end shimmy

[Stempy]

I have a rear end shimmy (no curry involved). When cornering if I hit a bump the rear end feels like it's going to lose it just for an instant, kind of like hitting a small patch of ice.

I am suspecting the rear subframe bushes as there is no noticeable play in the rear arms or wheels, and note that Citroen do a bush repair kit at £180 odd quid consisting of a front and rear bush. I have found that pattern front ones are available but yet to find the rear type.

Is it a fairly straight forward job to replace them? Looks like only one bolt to undo from the parts diagram but haven't had a close inspection underneath.