Vintage Necklace Chain Charm Identification

I am curious if anyone knows a research site which can help me identify the makers of vintage chokers and necklaces by their charm placed on the end of the chain where one would use a fish hook clasp. It is my understanding that items, although not signed can be identified by this charm they used on each necklace. Lisner, Coro, BSK, Sarah Cov, Napier and others have been attributed to different charms to identify their items. I have attached a photo of a 17" thermoset necklace which has this charm. I had the same charm on a choker last month. Does anyone know who's it might be and what source I might refer to to find others? I hate not to list the maker when I could have the information in my hands. Thank you for any assistance you might provide.

Jeffrey Broocks