Originally Posted by AlanAZ
The tensioner is expensive, even from Tischer. You can get both for half the list price from places like RMeuropean (although I'm noticing it's out of stock -- you may need to wait a bit), just google the part number. Don't forget to order the bolt, it's one time use only. Best to replace both pulleys, and the belt if it hasn't been done.
Thanks for the link, much appreciated!