So it did go to Singapore
It looks better then on the picture from auction house. It was auctioned (and bought) 1848, if we trust the tag on it. A nice example of older South-Sumatran (?) sheath, which perhaps could be also Madura Kacir. The blade looks more East-Java.
As I understand it at the moment, such arranging of Pamor is called Pamor Slewah. Note that this arrangement appears also on Gonjo.