In fact, they do show up used, occasionally. You just have to watch the hifi shark listings.
I believe The Music Room are Aqua dealers and may offer a trial period.
Their new price is $8320.00
Some who’ve upgraded from the much lower priced La Voce have said the sonic difference was not dramatic, despite the hefty difference in price but the La Voce has no tubes and as always, the "YMMV" caveat applies.