You can take the SelectedItem
and cast it back to your class
and access its properties
.
MessageBox.Show(((ComboboxItem)ComboBox_Countries_In_Silvers.SelectedItem).Value);
Edit You can try using DataTextField and DataValueField, I used it with DataSource.
ComboBox_Servers.DataTextField = "Text";
ComboBox_Servers.DataValueField = "Value";