Beacon Light Purchased—Can Anyone Help Identify It?

Recently I was contacted by a man who has purchased an old airway beacon light. He is wondering if anyone can provide details about it, or some tips on how he might go about finding more information about it.

The plate on the base is illegible. Lettering on the drum says “Department of Commerce.” That’s all the information he has at this time. He has no idea how to go about determining where it came from, nor do I. Can anyone help?