Nice looking keris coteng dress Max. I must admit that keris from this area are not my strong suit, but i do recognize this as being a good old example of this rather rare form. I will leave it to someone better versed in this area to try to pinpoint a date for you, but it has always been my impression (perhaps wrongly so) that the coteng was a pre-cursor to the tajong hilt style. Therefore i would imagine that old versions of it (as opposed to ones recreated in contemporary times) should have a reasonable amount of age. Of course, you don't show us the blade here which could be older than this dress, but if i had to guess i would probably place this at least as old as late 18th to early 19th century.