You want screens with IPS panels. The in-plane switching panels uses have superior color reproduction. You won't get away with paying less than $250 for one, though that price is far better than they used to be.
I don't think NewEgg shows what panel types are in the displays, though, so you might be better off browsing Dell's website.
Either way, you'll want a Dell Ultrasharp, a NEC, or an HP ZR series monitor if you want a nice screen.
They're not cheap.