Focal and Dynaudio speakers are good in that price range. I wouldn't bother with a sub until she settled into her own house and wants more than great music, like surround.
For amps, I am growing to think big receivers are pretty pointless when most of us have one or two sources and bluetooth. Hell, I argue a decent 100 watt, or so, digital amp with Bluetooth and two analog inputs would be ideal, she could then spend more on the speakers and upgrade in the future as she learns more.
I could certainly build something still able for that price, perhaps with a 9" - 10" woofer and a killer tweeter. Plenty of output and deep bass in one mid-sized package. I could even put a brightness switch on the crossover to choose between a natural sound of a brighter retail sound.