If you go to a car paint specialist they have a scanner that scans the paint .
They will then mix a small bottle with a brush in it or a spray.
Get the spray and just spray some in the cap and dab on.
The spray is handy if you need to respray the whole head.
The pigment of the paint might look the same in daylight.
But under artificial light you can see the difference.
You can tell on a car if it’s had a door or panel painted so usually they do the whole side of the car.
You play golf in daylight so it shouldn’t be a issue if you don’t look to closely.
Bling Your Swing for a full refurb is a far better option, see the review I did yesterday. Work is absolutely top drawer plus when you're not going to get a game for a couple of months why not treat yourself and the putter and have it back brand new looking.