Hi Alex, kind of. We know how's many were made, approximately how many were silver plated vs. nickel plated. etc.

A 6000 series Naval was probably built in the early 70's.

Basically you want to stay away from any Naval numbered over 14,000 and any Air Force dagger over 30,000.

I suspect you know about pre 1989 eagle and post.

http://www.worlddaggers.com/