if you are on about the 1 peice upper part of the sill trim VW as most second hand ones will be starting to suffer from rust bubbles about £30 ish each
it has a code you can put in on the door lock but you will need to find it out probably from the main dealer 4 truns left 2 turns right 1 turn left 4 turns right that sort of thing
8.5 to 1 spacers are 2mm thick and you can get them cheaper and thicker for lower compression ratio for nearly half the price of mine which was purchased in the UK for £100 but i dont know what the quality is like on German Ebay