That's a cool old headlight. That should have some real value to the right person. I would try to use it if it were me. The markings on the lens (E) may indicate a European heritage. It looks like an "A" in the middle. The silver on the reflector has some corrosion but looks ok.
The bulb looks to be an older European bulb as well. The tabs around the bulb are going to dictate what fits. The H4 bulb tabs are different spacing and widths than the others. A little research on old country bikes (and cars) might lead you to the answer. Sorry I can't provide any positive identification.
