“Period-correct” does not mean “original to the instrument”

A “period-correct” component belongs to a type and period consistent with the item. This can matter in restoration, but it does not mean the component was originally fitted to that example.

Distinguish at least three cases: original to the example, an original replacement from the same period, and a modern compatible replacement.

Functionally, all three may work very well; historically and from a collector perspective, they tell different stories.

When documenting a restoration, state exactly what level of originality you can support.