As you speak of, both the genuine g40 steering arms and track control arms are rose jointed 'internally' and ball jointed 'externally' (if you see what i mean). It seems that these genuine G40 parts are discontinued/obsolete from many VW dealers, however available through some/others as has been bought to my attention recently. It seems to depend on availablity and luck....
My dealer, like most, will tell you genuine g40 steering/lower arms are obsolete but they can source non-g40 components which will fit and do the same job (nearly
)!