Close! See if you don't agree with me that it's a
Reed Contrabass.
They're quite unusual, so obscure that we don't have much to go on as to how they sound - or didn't, the last time I looked, but now there's this bravura performance online, Reed Contrabass with Recorder Ensemble on
Let's All Sing Like the Birdies Sing.
I had a chance to play a contrabass sarrusophone very briefly years ago, or try to play it anyway - it struck me as a pretty feeble contrabass. In the semi-famous Sidney Bechet contrabass sarrusophone solo, he sounds like he jumped right on the mike. The reed contrabass has a much wider bore, which I guess gives it more volume - enough to keep up with recorders, anyway - but at an obvious sacrifice in tone quality and pitch stability, so you have to practice like crazy, just to sound as good as a reed contrabass can sound, which is not very good. And I imagine you have to manufacture your own reeds.
Clarence Williams' 1924 record,
Mandy, Make Up Your Mind, with Sidney Bechet on contrabass sarrusophone.
Note that the instrument for sale apparently is missing its "bocal", and it's going to be awfully hard to find a replacement! That's the equivalent to the "neck" of a saxophone, and of course its exact dimensions are quite critical to the sound quality, such as it may be.