Yes, they certainly did exist - I don't know whether they are currently made. The nose of the hose was a snug fit into the neck of the funnel lid of the tank. However, using it that way meant you were bound to accumulate a puddle of water of uncertain cleanliness in the funnel around the hose. So I have always used it with the tank lid off, pushing the end into the centre column. The rinse water is then forced through the film from the bottom up, exiting over the tank sides. However, the hose is not such a tight fit into the centre column, and frankly you might as well use a piece of rubber hose without the special end.
One useful thing about the design was that it was a tight fit over the lower end of the Paterson filter funnel, allowing you to reverse flush the filter screen.
Online auction sites are probably your best bet.
