I had this happen to me about a year and a half ago so thought I would add my story..
door mirror cover ( smashed into 13 seperate pieces following clonk from inpatient nutter travelling towards me at 45 mph ).. Yes I was sad enough to stop and pick up the damaged pieces and then also count them
R82 00 000 507 - n/STK Shell Mirror = £28.52
Sprayed by local carbody shop = £10
Simply clips back on - job done