Unfortunately I scratched the edge of two my CUPRA copper cup wheels recently. I have found a company called Full Moon Alloys in Preston Lancs who have done a fantastic job in refurbishing them. They are powder coating specialists and tell me the only way to refurbish them is to start again basically. The copper finish is slightly lighter and the CUPRA logo is slightly different, so best if it’s two wheels on the same side, but pretty cheap at £120 plus vat.