Welcome and congrats! These kris are addictive though...
I also believe this is a Sulu kris (kalis seko) from around the turn of the (19th) century. Really a neat twistcore blade and also the round pommel (bunti wood) is a rare feature! Only the remaining grip wrap may not be original - maybe a makeshift repair. I'd consider to have it wrapped in traditional braided and "lacquered" style. The blade certainly deserves a careful etch: a little diluted vinegar (keep repeatedly working with a plastic brush) will take care of any remining rust and a following etch with hot vinegar may be enough to enhance the pattern; the result will be traditional - maybe kinda subdued though. You may also want to try a ferric chloride etch (neutralizing much more important with this approach) or other approaches to get a more bold pattern (I'd recommend vinegar first which is much safer). Please try the search function with kris and, as the second keyword, vingar or ferric, respectively; that should get you to several threads with detailed info. Please ask if you need any additional info!
Just need to be the first on record with this plea: If you ever decide to part with this kris, please be so kind and let me know!
As mentioned, it's well possible that the budiak also has twistcore - if it doesn't show any visible pattern already, some hot water may bring out the laminations enough to verify their pattern. With a few close-ups we can work from there...
Regards,
Kai