Hi
yep lost mine as well and got a replacement from BMW Motorrad, now before i give you part numbers, when i got the replacement it only came in matt black, not the shiny black that was the lost one, but, when i put it on it looked better so ordered the other side and i think it looks better, a trick for making them fit better, order new grommets as well - push grommets in so they click in place then just swivel them to make sure they are bedded right - once you have done all 4 just pull the metal tabs towards you slightly - as when you push to click on the plastic body the you can really push and it will bed properly - part numbers Grommets 44 63 1 453144
side cover RH 46 63 9 445052
axial securing clip 07 14 9 239251
R18 Badge 46 63 9 829366