I have an '08 clubman S that I'm trying to find upgrades for (headers, downpipes, pulleys etc) but I'm having trouble finding those parts for the clubman specifically. Do engine parts from R56's fit on R55's? If not, where's the best place to find them?

 

Yes the engine and engine bay layout are identical in the R55 and R56 (assuming the parts are for the N14 engine) so they'll fit