Hi Dave,
thanks for your response. I have actually managed to identify the clip, when I set about fitting the replacement inner, lower LHS front wheel arch. I realised that when BMW supply panels of this type they would normally come with all the clips/spire nuts that would be connected TO by other panels. The clip in question, which was not only broken, but also bent, actually would normally be supplied with a front bumper, because it is clipped on the bumper and is there for the panel I was fitting to be screwed to. The reason the Part Advisor at the local BMW dealer was unable top identify it was because he was only looking at diagrams relating to the inner panels.
I sent him the attached pdf from which he readily identified the clip which has been ordered, and I will collect tomorrow (Saturday).
Thanks for your input.I have downloaded the appropriate page, after realising that my 2003 530i (E39) "Individual" is listed under "Classic" (Does that mean I can enter it into next year's London to Brighton Run?), so I will know exactly where to go. The clip in question is the sixth item down on the right edge of diagram headed "Bumper Front". (Also attached).
Easy when you know how! Really good advice, thank you again.
Tony N
P.S. The colour of my, similar aged to your, BMW is also blue, but described as "Nachtblau".
Unidentified clip location.pdf
Bumper Front.pdf