I found this link (unfortunately, it's in Italian) about Fratelli Gondrand perfins. I can't find a similar illustration in the content that compares to the one shown. The closest seems to be F64 (page 8) but it's certainly not the same as on the stamp scanned above.
Could it be one of the perfin types for which an illustration is not shown ... or is it a different perfin entirely? (It looks like an "F.C." to me and not an "F.G.".)
http://www.perfinitaliani.it/MODO/GONDRAND.pdf