Is there a Swashbuckler archetype that gives Magus class abilities? Or a Magus class that gives Swashbuckler class abilities?
I Do not Believe there are any architypes that do this, But the "Flamboyant Arcana" Magus Arcana gives the Magus Opportune Parry and Ripost; and the "Arcane Deed" Arcana lets you pick up other deeds as a Magus.
Best bet might just be inspired blade swash1/magus X.
The PF unchained variant multiclassing can give out magus class features.
While flamboyant arcana works, as part of nerfing arcane deed (so that it couldn't be used for precise strike) it was rendered largely useless.