I found this wavy blade at a Dutch collectors website. They look for all sorts of excavated items but couldn't determine what this is.
It looks like a short version of the Flamberge swords.. but this is far out of my field of expertise
Maybe some other members can shed light into this subject.
No dimensions or other pictures are available but they are very eager to assist according to there website.
http://www.dutchartefacts.nl/?page_id=322