I would agree with the general consensus here so far. If you can manage to adjust this hilt so that it fits with the proper orientation my inclination would be to use the hilt that came with the blade. It's just my personal perspective that collectors of SEA weapons sometimes seem a bit too enthusiastic about changing the history of the blades we collect with upgrades (especially on keris). Certainly as a Western collector i am even more wary about changing out parts if it is not absolutely necessary due to them being either completely worn out or missing. But if i have a blade with a good, solid example like this i would certainly think twice before replacing it. It does seem to happen often with kris that we end up seeing ivory pommels on low quality blades like the one you are planning on swapping from. I think this often happens when dealers want to make a kris more appealing for the marketplace and they have a spare ivory pommel laying about.
Also agree with Kai that you should take care of that rust on the tang, though i would image you were probably already on that.
I also concur that you should show the whole blade. Sort of a tease to draw attention to a twisted core and then not properly show it.
