Seeking Help in Identifyling Keris

[kai]

try to boil the blade in salty water and then after 30 or so minutes, start using a brush with hard plastic bristles to remove the black paint.

No, salt will be very tough to remove completely from keris blades which can be quite porous: Any chloride traces left will greatly foster rust development!

There is a reason why marine archeology of metals employs very specialized preservation methods that literally take years to complete!

Regards,
Kai