Based on your description I'm assuming the bushings in question would be items #2 & 3 in the following diagram

Item #2 p/n 1K0407182
Item #3 p/n 8J0199231
You'll also need new bolts for anything removed (i.e. items 4, 5, 20, etc)
See: https://www.lllparts.co.uk/catalogs/audi/RDW/ATT/707/4/407/407000

The wishbone itself is item #1 but I doubt the 'pin' is worn so I'd want proof that it was defective before I authorized replacement of that part.

If you do end up replacing item #3 you might consider installing an aftermarket anti lift bracket instead of the OEM part. A little more expensive but it will improve handling and reduce wheel spin.
For example see: https://superpro-suspension.com/au/...-arm-lower-rear-performance-mount-kit-to-suit-seat-skoda-vw-9995-aloy4343k.html

Whichever parts you end up replacing you'll need to perform a front-end wheel alignment so factor that into the cost.

 

I wouldn't mess around trying to replace bushes individually as the cost of labour is probably more than a new item.

https://www.autodoc.co.uk/lemforder/9666858

£139 for new arm complete with bushes. Obviously check compatibility etc with your car, and a job for yourself if your confident on the tools are a hours labour for a friendly garage to fit.