Identifying banjos with no name is a really hard job. I sometimes try to guess if the peghead shape is familiar or if the tone ring is an identifiable kind, but all you have on the last one here is "Bell..." on a metal plate. It could be "Silver Bell," in which case it's a really desirable Bacon & Day shell (though the description of the neck doesn't sound right, and B&D 5-strings are really rare), or it could be "Maybelle," made by Slingerland (as I recall), in which case it's less valuable but still pretty good (and they, too, made few 5-strings).
Or it could be something else entirely. Since it's an open-back, it doesn't sound like a modern Oriental Import© but an older kind of instrument. But the "Fender" peghead sounds a lot like it's either a modern oddity, like my GoldTone guitar banjo, which has a Fender Telecaster peghead (and a single-coil pickup, too), but the other possibility that occurs to me is that it's a really old banjo, from the 1850s-70s, and the peghead is a version of the "scroll" style seen on Boucher banjos and others from the Minstrel days.
How large is the shell? If it's big, like 12" or more, and made with one ply of bent wood, it might be one of the really old ones. Does it have brackets to tighten the head? How many?
Does it look like this?