You may find pencil skirts by Burberry's different lines at Net-a-porter and My Theresa :
BURBERRY PRORSUM
Ruffled crepe pencil skirt
BURBERRY PRORSUM
GLENCHEK PEPLUM SKIRT
BURBERRY PRORSUM / BURBERRY BRIT
Tinsel-striped pencil skirt
BURBERRY LONDON
Stretch-crepe pencil skirt