Ha! Good luck! There are a handful of us on this forum with Batavus bicycles who are still seeking positive dating on ours as well. Unfortunately, as you have likely found, there is very little information to be had on this marque online. Your best bet it to contact Batavus itself (responsive and friendly), though the company was apparently sold in 1986, and they retain precious little information on pre-1986 models. Another BF member recently contacted the company and was told a retired employee may be able to provide info. I think that's your best shot. Search "Batavus" in this forum to find our respective threads. The email address for Batavus is info@batavus.com

I second, East Hill. Would love to see photos!