Found this nice ISMLP category page while starting research for a new project, containing enough baroque French gurdy scores to keep anyone busy for a while imslp.org/wiki/Category:Scores_featuring_the_vielle

There’s all sorts of interesting stuff if you poke around a bit — for example, in Bordet’s Méthode raisonnée pour apprendre la musique there’s a summary of the hurdy gurdy which suggests that extended keyboards beyond the usual two-octaves-minus-high-F# existed, but were “extraordinaire, et peu usité:”