Historic brick tend to have two problems. They can be a different size than what is being produced today, and/or their colors may be too dissimilar to match well. This can make finding a good matching brick for repairs difficult if used originals are not available.
Many companies though, tend to struggle to match the color for discontinued brick. They may even tell you that you have no choice but to use whatever similar modern brick they can find and live with an obvious patch.
When unable to find an accurate match, we will find the closest brick that can be stained to try to blend the new and old together. Even joints can be stained. The results have proven to be far closer than most people will notice without looking for it.