SOLVED - YA classical novel set in mid to late 1800s [s]

[Tyler]

A young woman finds the costume of a folk hero (similar to the Scarlet Pimpernel, Scaramouche, Black Arrow, etc) while cleaning the house of an elderly (or deceased) widow.
Her family operates an inn, or she works in an inn.
She ends up using the costume to save someone from execution.

I read this back in the mid-90s, so details are sketchy

[Liralen]

Jackaroo?

[Tyler]

Liralen wrote: "Jackaroo?"

Yes! Thank you very much