Hi Russel,
nice tombak and more nice to have the scabbard, although I think that the tip of the scabbard is missing. How long is the blade without pesi (tang)?
Here is a thread which could be helpful for you:
http://www.vikingsword.com/vb/showth...ghlight=tombak
I think that your tombak is from Java, age difficult to say. A cleaning with lemon juice will remove the rust but you can use vinegar as well. A warangan (traditional stain) will bring out the pamor.
Nice piece, congrats,
Detlef