Long Machete-Like Knife, Replacement Reed-Wrapped Grip; Malay?

Overall length is 21 3/4", blade length to previous grip-line is 16", the blade is ~7/32" thick at the grip, tapering very slightly to ~3/16" at the spine break...where its depth is ~1 3/4". The wooden grip is ~4 3/4 long with a 90 degree leg of ~2 3/4"; the woven reed binding is ~1 7/8" long. The apparently hand forged, carbon steel blade is covered with an amber finish that yields to alcohol & acetone. It is dead-flat on the left face, saber-forged to 14 1/2" length on the right; above that the right face is very slightly concave full length. Weight is ~17 3/4 oz.
It was sold as Malayan, which may mean Indonesian, if at all accurate; I purchased it locally at a flea market.
I would like to know how long ago it may have been made, where, an' what purpose its profile suggests, an' especially what can be known about the reed work, please. I have little confidence about its origin according to the seller; I'll be glad to hear your comments...Thanks for lookin'!

 

Indonesian Tribal MANDAU Sword ~ Used by Borneo DAYAK Tribe Headhunters

 

older ones have terrific carved handles...

 

Indeed, Komo...as well as fine woven reed, with beautifully complex patterns. Thanks!
https://en.wikipedia.org/wiki/Mandau_(knife)

 

I think the type of handle depends on the tribe, Borneo is a huge island. Present day buyers often prefer the ornately carved handles, so there are also newly carved ones.