Ralphiano I agree that those prices are mostly high
These are the asking prices. Like in store, also in private sales the price is always negotiated, sometimes dramatically.
dore_m $15k for that 1917 Model A is actually pretty good, if it's been restored recently.
True, and if it's been restored well.
dore_m 30k for that other one though - wow
Again, one could negotiate.
CyberGene I envy how many good grands at great prices there are in the US...
That is true. I think I've already told the story explaining why, but I'll repeat it here: back during the "Golden Age of Piano" the USA was very wealth and already very spread out. Many places were remote enough that there was no entertainment opportunities. Having a piano was almost like today's having a 50" television. Many, many instruments were made and sold, there were astonishingly many brands (google that if you don't believe it). Most of them were 💩 obviously, but a decent percentage were good and the game of numbers makes that some are still decent today -- especially if they've been restored (an essay in its own wrt this word). Today, very few people care about pianos after grandma died, but they did not sell the instrument… until they need to sell the house and now the new owner wants it out by next week… Big opportunity, often (but not always) taken by the dealers… but dealer or private sale, it's a ceiling price.
On the other hand, Europe was not so wealthy to begin with, the higher population density made more opportunities for other entertainments, so fewer pianos were built in the first place. The WWI and WWII (especially the latter) destroyed many of the instruments that existed (like now in Ukraine) and hence you don't have this oversupply. Plus people tend to not sell the houses like crazy as they do in the USA, so there is also less pressure from "the new owner".
The good news is that there are a few dealers who ship oversea, like the one discussed at http://forum.pianoworld.com/ubbthreads.php/ubb/showflat/Number/3209284/gonew/1/piano-seller-in-lilburn-georgia-usa.html and I believe you also have one or two European "gray importers" like https://rickjonespianos.com/
Obviously, it's much more difficult, but you can do it if you're motivated (you'll have to hire a trusted, independent, remote technician, and you can do it, it's surprisingly easier than it sounds, I've done it a few times!) -- however I am not sure it'll be worth when you consider the VAT, shipping costs and other import duties, you'll have to investigate that yourself.