Hi ST welcome to NMB. Can you tell us if the hinge folds all the way flat and does not hinge towards the front as well? I think what you may have is a set of "tsuba bookends". Although I don't have the same style I do have a set of heavy cast iron tsuba bookends - They are ideal for keeping your tsuba books together! If it does turn out that your pieces are bookends, consider how rare they might be and that they have stayed together - a single bookend is not so great!
The pieces could be Chinese rather than Japanese - Chinese character 直 (zhí), which means "straight", "direct", or "vertical"
The imprint would not be a persons name but more likely a company "logo".