Ok, so, off on a BIG tangent I go, and don't be mean now, the parallels are purely visual speculation but hard to ignore visually.
I got thinking about how I see the Datu Hulu iconography, as seen above with the annotations.
I thought then to delve in to the the headrest image I shared and its point of origins being Cenderawasih Bay... certainly a Sarimanok to my eyes...
https://en.wikipedia.org/wiki/Cenderawasih_Bay
I went down a totally unfounded but very possible relationship in so far as cartography and the iconic Datu hulu goes, and overarching ancient spiritually belief of this magical bird, as represented by ... The PNG land mass which bares a striking resemblance in new maps and old maps of the period...
Is there something in this mythologically that we are missing?
I've no time today to go further down this rabbit warren in interest... perhaps others can?
From a cartographer point of view, is this very object discussed visually... tell me it's not
