Hello David,
First, it's a pedang. Sadly your pictures are a little bit blurry so I can't say much about the handle and scabbard (age) but would guess that it comes from Sumatra (maybe Lombok), blade looks good and antique.
I don't know what you mean with "A bit too obvious, it looks like it has been dumped in acid and then burnished with wire wool", do you speak about the blade or the fittings? When you mean the blade it will be the structure of the pamor blade I guess.
Regards,
Detlef