I recognize that one from the HOS exhibition.
These straight bladed daggers are, in my opinion, more likely to be from the Yunnan regions. But, as Gav notes, the modern geographic borders in that area are much less significant than the cultural/ethnic distinctions.
Older examples typically have better blades, often with inserted edges, differentially hardened edges, laminate construction and higher-quality silver.
Not sure if I completely agree now with the "early 19th century" attribution on that HOS example, but we know more now than we did at that time...
Probably late 19th/early 20th c.