i want to replace the rear plate light on my Rocker C with the tail light that comes on the european model rocker C does anyone know where i can get it from?

 

You might get lucky and find one on ebay someone has taken off their bike.
Or check here to get the part number and see if any dealer has one in stock.
HD'd site will come up blank since they are out of production, but a dealer might have a source for one.
http://partsfinder.onlinemicrofiche.....asp?make=hdmc
Put the part/assembly in your cart to see the part number.