Well... Ok, the inscription is horribly done... but that's it. Inscribed with a flat chisel and a round punch, probably. Plus the fleur-de-lis stamp, of course. It might be even period, done as an afterthought or by/for a Catholic user or who knows why. Or a sad atempt by a late dealer to add some kind of distinctive feature to a weapon of quite a common typology. And, yes, the wiring of the hilt is also probably a replacement (having it on hand would allow us to see how well the turk's heads fit, for example, as a gauge for this possibility).
But, to be frank, the rest of it looks fairly
kosher to me. Central Europe, 17th or even 18th century, "Walloon"-type hilt.
Oh, and, of course, it isn't a rapier
Just another opinion, of course
