I used almost an entire box repairing the damage caused by a water leak on the fridge icemaker.
Sorry, I know that's boring, but in the event they stop making that color/style, you'll have a back-up.
With laminate flooring there is always a chance damage will show up somewhere so it is a good idea to keep some around.
When I did a room for a friend we picked up a pallet of several cartons on special, the vendor warned us that the new lot, same name and shade would not lock to the old stock so to make sure it was enough for the job.
Wise men speak because they have something to say; fools because they have to say something -Plato
It was the dumbest thing that we ever did in the room addition. You can't repair the laminate. It can be scratched and all you can do is replace or cover it with a rug.
A bit of advice from the school of hard knocks.
If you are doing hard wood floors, install a good solid oak and DON'T stain it. In 15 or 20 years when you want to re-finish the floors all it takes is sanding and a couple of coats of floor polyurethane. My kid scratched the floor in his brand new house during move in. The floors had been pre-stressed and stained dark. Several attempts were made to try to match the color and we failed. Even a painter friend tried. There is a rug covering the scratch today.
I see laminate in many houses I go into and it looks great. Very serviceable and easy to replace and fix a section that gets damaged by water or pets. Having some stored away is a very very very good idea. I look at floor covering like it's something that NEEDS to be replaced every now and then. In my daughters 130 year old house the floor talks to you as you walk accross it. Going up the stairs is a whole concert in wood movement!
No floor covering is indestructible. Things happen. Same thing goes for vinyl siding. Buy extra and save it. Replacing damaged parts of it is easy.