This is from England, but if the price doesn't go too high it could be a very good buy, even if shipped to the USA. Very fine Imperial! Made in 1981 so it should have a large shank receiver, like most modern euphoniums. Seller's description of the horn:
Stunning Boosey & Hawkes Imperial Euphonium. Some light wear to the shiny silver plating, still looks amazing!, VERY few tiny chinks.1981, no leaks, beautiful sound, perfectly presented, completly serviced and cleaned. Fast valves, no rust at all. Guides great, new springs corks and spring dampeners. Original low pitch, used but great condition 4AL mouthpiece (large bore), nice modern immaculate Besson case.
https://www.ebay.co.uk/itm/163699693371

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