Hello Robert,
great catch!
It was on my watch list but I was irritated by the leather scabbard which coming with the dagger, now I am sure that the scabbard isn't worked for this piece, don't coming from Luzon and is much later.
I would place this very nice dagger around 1900, maybe earlier. I am curious to see better pictures after you have received it.
Best regards,
Detlef