If the timing belt has not been replaced at the suggested maintenance interval (originally 100,000 miles, now 80,000) and you are currently at 126,300, you need to have it replaced as soon as possible. While performing this job it is highly recommend you replace the roller, timing belt tensioner and waterpump. I would also recommend replacing the serpentine belt at the same time. As for the oil pump gear kit, better known as the balance shaft module (BSM), it should be converted from the chain driven BSM to the gear driven BSM at the same time to save on labor. The original chain driven BSM is a ticking time bomb you cannot afford to have go off.
Where to buy a timing belt replacement kit - there are several vendors that frequent this site. In no particular order ( I apologize if miss someone):
Selling kits
www.dieselgeek.com
www.idparts.com
www.worldimpex.com
www.boraparts.com
VW dealers that sell the individual pieces
www.gunthervw.net (search for this site for code for discount)
www.1stvwparts.com
The question that accompanies this, who are you going have perform this work or are you going to attempt yourself? ...most [assume] VW dealers don't even know the problem exists.
Read the stickies at the top of this forum for more information BSM info:
http://forums.tdiclub.com/showthread.php?t=233651
http://forums.tdiclub.com/showthread.php?t=293773
Other things to check at the same time (cuz you are there):
- Alternator pulley
- Engine mounts
- Check to make sure the ground cable isn't rubbing on the intake charge hose on the front passenger side
- Electric cooling fan at radiator is functioning
- mechanical cooling fan bearing and hub or in good working condition
