Wheel centre-cap, Rover 57mm.

[jeff turbo]

All sorted now thanks to 'ceedy'.
Incidentally, for anyone else looking, I did find some NOS ones in France at www.abpparts.com.
Good source for screws, clips, fittings and "odd bits" like that centre cap, as long you have the part number, (thanks for that tip, Jeff).

David

No worries, a good site that, still has plenty of parts