Its probably just the bushes but its cheaper and easier to replace the whole wishbone, which comes with both inner bushes and the outer ball joint. Circa £30 from all the usual suspects.
Perfectly doable at home, just the usual fun related to parts that have been exposed to a decade of muck so be patient and use plenty of WD40 before butchering the nuts and bolts.
Hardest part is getting the new wishbone into the fairly narrow gap at the rear. The new bushes don't want to twist as easily as the old ones so you'll probably need a mate to help you ease it into position and get the first bolt started.
No it won't add significantly to the time if you do the pads as well, just do both sides.
GTV and Racing Driver