All,
Here is an e-bay listing for a Besson 2051 not owned by Demondrae Thurman but owned by Patrick Shulz and played in Sotto Voce as confirmed by Professor Thurman.
Besson 2051 Silver Euphonium- Made in England- mint condition | eBay
I'm not affiliated with the listing but thought someone should get a shot at it if they were looking for something similar.