I'm a big Vandersteen lover. I don't know why more people aren't. But that can be good since you can buy 2C's between $400 - 650, depending on condition, and where you are in the country (local market). I can tell you that I have owned the 2C's and now the 3A. When I got my 2C's, I was in a 10x10 room with wood floors and slanted roof. Easy to dial in and easily the best speakers I have owned up to that time. I kicked out some JBL Jubals (L65), Dahlquist DQ-8, and a few others. Vandersteens are fairly efficient, and are designed to be forgiving towards the source power. Case in point, my brother in law just picked up some 2C's for $400 in 8.5/10 condition and running with a Pioneer SX-850 ... they sound great. His mind is blown.
I loved mine so much, I jumped on a mint set of 3A's from the original owner. I was in a 15x20' room, but now in a 9x10. I have them positioned so they still sound great. Of course, I can tell they would bloom more with more space, but that will be next year in the new place. But I'll tell you that if you do buy Vandersteen, make sure you get some good quad cable (Canare) and bi-wire. I know the idea doesn't seem to make sense, but I've done testing in my own system, and found it does make a slight difference. Enough to be worth it.
If you like mid century modern look and want something off the ground, I would take a serious look at ADS. They have butyl rubber surrounds on the woofers, and I have never seen a bad one. Some models are better than others, and some have metal grills, and walnut veneer.
Dahlquist makes some good shelf speakers like the M-905 and M-907. Build quality is good, they use good drivers, and they are under most people's radar, so you can usually find a good price.
As you can see, I'm not a big fan of new speakers, for your price range. You can buy so much more speaker for that kind of money, that are built like furniture, and hold their value better. Just buy smart.