Compare the pictures here of what I think is a Thai darb (perhaps PUFF might confirm the blade inscription as Thai) with the rear horsemen's swords in the picture of the
bas relief above that Mark B. posted.
This sword is interesting in that it is quite long, consistent with many cavalry swords, widens a little towards the tip, and the tip turns up slightly on what is otherwise a fairly straight blade. The hilt is a three-part construction and of oval rather than circular cross section. A sturdy iron ferrule adorns each end of the wooden handle, and there are iron plates covering the ends of the hilt, each secured by two nails.
There are engravings on the blade, with an inscription at forte that may be a person's name (help needed with translation please).
Based on the swords shown in the
bas relief, this style seems to be quite old, perhaps dating to the 13th C or earlier.
Overall length = 88 cm
Length of blade = 58 cm
Length of hilt = 30 cm
Ian.