how can i fix my gearshift selection on an 06 VW t5 transporter?

I lost the ability in my van to select 2nd & 4th gear. 1st, 3rd, 5th and reverse all still select but from the "neutral" postion on the selector. Dealerships aknowledge that this common but wont provide details of parts. Must be taken to them for diagnostic and a huge chunk of cash. I have been told that this common problem is due to worn bushings specifically the "guide bush" & "bearing bush". can any one confirm this and possibly supply part numbers?