Serepta: This is a spelling variation of Sarepta, which in the KingJames Version of the Bible is used as the name of the town where Elijah was sent to live with a widow when Jesus mentions that Old Testament story in the gospel of Luke. In more modern translations of Luke the Old Testament Hebrew form Zarephath is used for the place name; Sarepta is the Greek version. Sarepta was regularly used as a female given name in the USA during the 19th century.
Junis -- undoubtedly just a variation or even a misprint for Junius. (See Junia in the BtN dictionary.)
Elminia -- This is a 19th century invented name. Many American parents were as fond of creating new names beginning with El- 150 years ago as some were in the 1970s of creating new names starting with La-. Elminia is a blend of the sounds of names like Elmira and Lavinia.
Levinia -- and this is just an alternate spelling for Lavinia
Lavonia -- a blend of Lavinia with the European place name Livonia (now divided between Latvia and Estonia). This may have been as much the result of mishearing or misremembering as deliberately creating a new name.