This lovely snaphaunce appears Italian to me. Examples would be Fig 4, Encyclopedia of Firearms, Hrold L. Peterson; Jackson & Whitelaw in European Hand Firearms state ". . .by far the most beautiful snaphaunce weapons, comining the finest of workmanship with artistic decoration and elegance of design, were made in Italy (chiefly at Brescia) about the middle of the XVIIth century, at which time the art of chiselling in steel was brought as near to perfection as possible." See figures 35--42.
Be interesting to see the rest of the gun. Is it Italian, or might it be a Spanish gun made using that old Italian lock?