Great swords! Really.
This is why i try not to go on record dating these things. My own opinion changes often. That said, I do feel this one be older than that estimation. But maybe a bit younger than mine. There is at least one example in the National Museum in Bangkok with a Japanese-styled silver handle attributed to the Ayutthaya period. With so many different styles of swords worn by so my different groups, I have a hard time with hard rules...