Any automotive aisle of a big store. Here in Canada it would be Canadian Tire, in the States - don't know, Autozone maybe. Walmart might have some too. Small $5 cans of spray-paint for practically all cars sold in the last 20 years. Hundreds and hundreds of cans. Color shown on the cap. You are guaranteed to find one that will be "close", will blend nicely if you only paint a small scratch.
Being a spray, it's not easy to paint "small", but if you spray onto a piece of rug and touch the scratch this should work. Better than nothing.
They also have VERY small jars of touch-up paint with brush applicator. Can't say about touch-up pencil, never used one.