Hello Ariel,
it is not a keris bahari but a keris panjang, both keris have the same blade profile while the keris panjang blade is longer. Some people call this keris execution keris. The keris is from Sumatra.
The blade seems to have old rust, not active so far I can see from your pictures.
The varnish seems to my eyes (dirt-) patination maybe overpainted with some sort of finish.
The reason is maybe that the stem (by javanese keris called gandar) is a later addition since the original one was broken, but this is all only a guess since I never have seen such a "gandar" by a keris panjang.
When it will be my keris I would clean the blade in lemon acid or pineapple juice. The scabbard I would let in this state since I am very unsure about the stem/gandar. But the upper part normally have a very very nice wood.
Here a thread where you can see three other keris panjang:
http://www.vikingsword.com/vb/showth...hlight=panjang
But with the search word "panjang" you will find more.
Regards,
Detlef