05 jetta is a BRM motor, they eat cams just like BEW and BHW motors do. It not terrible to do a replacement but its around $600-800 plus timing gear. Get an aftermarket regrind from Frank's TDI's or Colt(order from Colt direct), they fixed the problems with these cams.
PD motors have been around since around 2001 in Europe, they never did fix the cam problem or do any recalls. We got them in 04.
Two good oils I use are Rotella T6 and Mobile 1 Turbo Diesel Truck. There are lots of other good oils but the price goes up quite a bit.
You can get the two oils I listed at any walmart or auto parts store, at least around me.
Do you plan on doing any upgrades?