yes its 100% a 8mm square peg drive and yes halfords do have them , but they only had a 3/8 drive one.about £4 it cost
i have just had all this hasle when i went to do a oil change and thought a 3/8 square peg will do.
some idiot had really tightened it up and my short handled 3/8 rachet with the 8 mm socket on wouldnt move it
so i ended up getting a 1/2 to 3/8 drive convertor so i could use my longer 1/2 rachet on it
jobs a good en now.
thanks to the people who said a 8 mm.!
i thought i would just confirm it again for other people and that was on my clio 16v 1.2 -------y reg