There is a Cammeyer Patent model zither-banjo in Yorkshire, up for auction on eBay.
https://www.ebay.co.uk/itm/373471537165?ul_noapp=true
It appears to be in good condition, though I haven't studied the photos carefully. It lacks the fancy resonator and that is just as well because by now these have all become a mess on every specimen I've seen. And it has heel carving!