They originated in Finland, so some of those brands might be out there if you figure out to search for them on their brand name.

Pro tip: I find on eBay that when I'm looking for things if I don't use the exact name of the thing I'm looking for I can find the products that people didn't know what to call them. They're out there, orphans waiting to be discovered. Don't search on "Steam juicer," search on some of the product names instead. Or even things like "Pot with hose," etc.