I think you would need a greenhouse for them as they originate from Brazil and parts of Central America. Good luck with your search for one of these.
I am posting a picture here of another flower also called the Dutchman's Pipe.The brown and yellow flowers,hanging down in long sprays are very attractive. The climbing plant is really big and needs a large sturdy frame to grow on as the woody stems may reach the size of a man's forearm.I'm not sure whether it is an Aristolochia.
Talking of big the second picture is of a tropical begonia, better known for its foliage than its flowers, with its clusters of flowers and growing oer 8 ft tall!
Both the pictures were taken in the Cameron Highlands.