Straight Parang Nabur or?

[VVV]

I found these reference swords, collected in Borneo, in the Leiden Database.
Usually when I find odd swords in museums and collections there is only one of them.
But in this case there was five so it seems as if it's some kind of Borneo parang not covered in the reference books?
Could it be a straight blade variation of a Parang Nabur (like the more usual straight Piso Podang) or something else?

Michael