Check out my good friends at Rogue Music - 220 W 30th , Between 7 & 8th ave.
They have a good selection of used gear, although they have not seen many used Kronos yet. You can also get on their mailing list. They ship worldwide!
there is some variation on state sales tax based on the state from where you buy a new Kronos.
Then there is shipping ( air ) back to your country.
I recall this being a frequent topic. If you buy the keyboard in the US, any warranty is performed here in the US. Thats my recollection from older topics.
And yes, a few owners have needed to use the free Kronos warranty.
I was looking kronos in Miami on the net and it is more expensive than in NYC...
The thing is that I will not shipp the Kronos to Europe I will drag it with me so I will avoid shipping cost....