He is looking for the "brake circuit failure" switch which you have to be reset whenever you bleed the brakes (right?). The one that screws into the brake line distribution block on the inside of one of the fenders. Try www.gcp.se if the site is up. They've been down a few times during the recent floods in Europe. The part number might have changes, so have a look through the parts catalogue of GCP. Get the price in Euro, because selecting a different currency is biased to protect themselves. Is it not the same as on the 240? The brakes on my '71 144 and '88 240 are identical, except for a very slightly different master cylinder and vented discs instead of solid (but same brand). If so, try www.eurocarparts.com in the UK. Is your switch bent? Always unscrew it before bleeding brakes, then it will last for ever.