As I peruse ebay, I came upon the “stethoscope” advertised below.
Flexible monaural stethoscopes were introduced around 1832. These were tubes of coiled spring covered with woven silk, usually 14 to 18 inches long, with a chest piece at one end and usually a very short, straight earpiece at the other.
Flexible stethoscopes are often confused with conversation tubes, which looked the same, but were much longer than stethoscopes.
While I do collect antique hearing devices, I may inquire into this one but not for $450.
I happen to know the seller who is a very nice guy but I am 99% on this one with my source being http://www.antiquemed.com/mona