Looking at the shape of the blade, I still would vote for Sumatran.. ;-)
Also I have seen several Sumatran pedangs with horn hilts in the shape as this one, only plain without that beautifull floral design carved in it.
I am still thinking that the handle is horn, as far as I can see on the image, but I can be mistaken ofcourse.
Horn by the way is used on all the islands of the indonesian archipellago. I am not sure if it is correct to say that when it is horn, it probably is Lombok.
In Sumatra also a lot of handles are made of carabao horn...
A friend of mine has 6 of these pedangs in his collection. All with gold and suassa and complete with scabbards.
Two of them have upward curved blades, and the scabbards of those two are both plain wood.
Three of them have a similar scabbard as the one Vandoo posted. One scabbard with no decoration at all, one with a suassa scabbardtip and suassa scabbardmouth, and one with a silver scabbardtip and silver scabbardmouth, and one silver band in between.
But none of the 6 have very highly decorated scabbards with gold as you would think it should have....