I owned one identical to it, maybe 20 years ago, and must have sold it off long ago. I never did figure out its origin, but didn’t try too hard either. ?The secret is in the crown. The crown is very distinctive and if it is real, it is the crown of one monarchy only, if you can find a reference on crowns. It is probably a ship’s bell, if it is real.

If it is an authentic ship’s bell, it will be bronze not brass. If you want some opinions on its authenticity, post some good pictures of the underside showing the clapper and how it is hung. That’s the area where fakers take shortcuts that can be revealing.