Well, you guys asked me to let you know what I got for the Horn in the
end. To bring you up to date, I lucked into a Horn of Hsagra, doing a
low-level quest in Ak'Anon (probably due to a loot-table mixup). I offered
it to a friend of mine who is in a guild, and he said to write my own
ticket. So I did. I requested the Lute of the Howler, and some coins for
the Nostrolo Tambourine quest. I didn't expect to get all of that, but I
was hopeful.

Today I got a call, requesting my presence in West Commons. There, I was
presented, in trade for the Horn, a bag containing one Lute of the Howler,
6 Ancient Coins, and 18 peridots.

I'd say I did well.

Talies the Wanderer

P.S. What level can I use the Lute's illusion?