Here's a pretty good buy on a nice-looking New Standard. It has a 444xxx serial number, so should have the medium shank receiver that many prefer. Includes a hard case. Offered by a very reputable seller with $60 shipping. Buy-it-now price is $1,595.
ITEM SOLD FOR $1,595
https://www.ebay.com/itm/GOOD-ENGLISH-BESSON-3-VALVE-COMPENSATING-SYSTEM-EUPHONIUM-WITH-WARRANTY/122912332614
More photos on the listing.