That looks like a good job though, I can just see the area on the chainstay but only by making a close look.
I see in a number of posts on the site that people recommend not going to Halfords, and I totally agree. The Motorfactor industry is overrun with overpackaging and having to buy multiple small items; gone are the days when you could go to a small privately owned specialist factor and buy one small item - we also need proper ironmongers again 'fork 'andles' etc. (One of my all time favourite comedy sketches
Some main dealers still do touch up bottles but at a premium price. What I found recently was a few firms on the Internet who mix small touch up bottles to order for a known colour, either by paint code or car registration. So all you have to do is ride around until you see a car that has the right colour and then either research the manufacturers paint code or, if it has not been resprayed, write down the registration number.
I found a number of firms by googling for Car Touch Up paint, prices vary from £5.99 to £9.99.