Yes, I'm with you on this one, Godfried:
If both sides of the blade are (convex) rather than )concave+convex) and it's stylistically Iban rather than a few ethnic groups limited to Sabah and northern Kalimantan Timur, this label seems suitable...
Is it known from where in Brunei this piece hailed?
Very detailed work on this blade! Backside of the blade as well as scabbard?
Regards,
Kai