Hi Willem,
very bad piece but I will be neat and you can send it to me that you don't need to look to it again!
But seriously a very nice keris and Laowang could be correct, look also this thread:
http://www.vikingsword.com/vb/showth...4&page=2&pp=30
I don't feel prepared to say if this keris have the original sarung like you think or it is a composite ensemble but I think that you have hold enough keris in your hand to decide this.
Regards,
Detlef