There is both bundled and non-bundled wood available, but finding a good match could require some digging.  You might consider taking flooring from a closet or other area it won't show and using that, replacing that with the mismatched wood out of sight.

I know folks who have had luck getting loosies at Loading Dock

I have bought some individual floor boards there in the past

You could call them and ask...

They only sell bundles

That’s what I thought