Well Alan, i understand you reasoning here, but it's more than the finish that makes me think Bali (or Lombok). The pamor pattern and execution look more Balinese to me and that single fuller reminds me of some i have seen on Balinese keris pedang. Also, while i have never seen hilt motifs quite like this one it doesn't seem to say Jawa to me. But of course, this is all just speculation.
I do believe that what we can say with a fair bit of certainty is that it is NOT a European blade or a dha and that it is from some part of Indonesia.