This is a genuine VAG offside rear door bump strip moulding to suit 5 DOOR models, late 1984 to 1987 small bumper Golf GTI Mk2 8V and 16V (Type 19 models - photo of mine used merely to illustrate the model this suits)
VAG part no. 167853754 QS2 (satin black/mars red) - obsolete worldwide brand new
It is 40 years old, please scrutinize the photographs, The red stripe has faded but easily reinstated with some Mars Red paint, there is some age marking to the black rubber too but no significant scuffs or gashes. Will need new double sided tape.
Probably No good if you think your Mk2 is worth £10K+ plus, if you don't then this might be of use and certainly better than having a missing moulding altogether.
Please see my other listings.