SLK/R170: SLK Flashers
If you get a new one, it has to programmed by the dealer to blink to U.K. specs. If you get a used one like I did, just plug it in, takes all of 5 minutes to replace. Check salvage yards in your area. I paid $125 U.S. plus shipping about 2 years ago.
#17 in this picture, has part number too as well as list price from many years ago




