Hello,
I'm not sure about the origin of this Klewang.
The handle and the blade make me say that it comes from Sulawesi, but the sheath isn't in the Toraja style (for the little that I know).

The blade is very thick at the base (1,2cm) and heavy. It is covered by a yellowish varnish (shellac?).
Total length of blade : 51cm
The sheath is made of light-colored wood and has been tinted. It is clearly visible at its point where it seems to be missing a kind of chape.