Any automotive paint supplier will mix you a touch up kit or rattle can, far cheaper than a dealer + if you take the car/ caravan they will get the colour shade right. Purchasing a touch up kit from a main dealer or Halfords won't guarantee a good match, especially with reds and yellows.
My preferred method for touching up scratches and chips, is to apply the base colour with a touch up brush and spray the clear coat over a larger area with a rattle can , let it harden for a few days and cut back something like a Farecla G3, then a G10 (or equivalents) . This should give you a good repair at a fraction of a PDR cost. If you have any runs from the clear coat, let them harden, and shave off with a razor blade prior to using the cutting compounds.
If you have 3 stage pearl its more difficult to hide the repair and may need a bit of trial and error, if the panel has had a previous repair and was refinished in 2 pack, or if the damage is deep (2 pack chips can be like craters) , a smear of stopping compound, will be required prior to applying the paint.