Hi Grissly,
I have used Chipex for this kind of wear and tear.
It comes as a kit to enable you to do a number of chips and knocks.
You should be able to fins the paint colour and code on the site.
http://www.chipex.co.uk/ I think it may be this one, but please check. You can try entering your reg as well to cross check.
http://www.chipex.co.uk/colourmatch/sear...code_selection=