Thanks, Puff. Example #3 looks very similar, with the flamboyant prong at the base of the blade.
Dan Wilke was able to sneak some photos of the Royal Museum's collection and shared them with us on this thread:
http://www.vikingsword.com/vb/showth...ht=thai+museum
In one of the last photos, he was showing some keris, but you can see some mounted pole-arms below it, including a spear and the tops of two blades that look very similar to the one we're discussing.
Andrew