VVV's keris is a coteng. The hilt does not have a beard, and has a very 'flat' head. Tajongs have boxier heads and a beard. This coteng is unusual in that it has that highly exaggerated garuda mungkur at the back of its crown. The sheath is of a very old form. Its amazing it survived. Please take extreme good care of it because it is very rare. Try not to do anything drastic to it please. The blade is of the pandai saras form. However, most cotengs I've seen do not come with pandai saras blades. They come with this sort of blade:
Hence, there is a possibility (I'm not 100% sure) that this piece may be 'put together'. Even then, its well-fitted, so it still looks good. Some Bugis-influenced blades can also be found in coteng kerises.
Cotengs and tajongs are very closely related. In some cases, they are almost hard to tell apart:
The above hilt is boxy like a tajong, but has no beard. Even more confusing - the sheath form is usually associated with cotengs.
BSMStar's hilt is probably a modern reproduction made in Indonesia. The beak is not too correct, and the "front-view" proportions is not quite correct. The hilt was probably made based on a photo, because the proportions are more or less correct when viewed from the side, but not from the top. Plus, the motifs on the hilt looks very S. Sumatran, not N Malayan.