I don't but i went to their main unit (Unit 4, Maple Industrial Estate, Maple Way, Feltham TW13 7AW). Ok so it's not that close depending where you are in Hampshire but i would say worth a trip just so you can get an exact match while you wait. Alternatively you could send them a scrap of leather/headrest so they can match.
When i spoke to them and gave them the leather code for Alpaca Gray they said there can be slight differences so they like to match direct. I think this is one of those cases where you want the best match possible so any "repair" is unnoticeable. Honestly with mine there is no way you can tell where it's been restored. They match it by eye - quite incredible.