700.00 speakers new or used

Omega Super 3i Monitors $695.

Small and efficient single-driver (94.5 dB) plays well with both tubes and solid state. I can listen to these all day with or without a sub in the mix but adding a sub adds that foundation we often miss with such small loudspeakers.

Another + for the Maggies (I have the older MMG’s).

First off do you live in an apartment or home?
Do you want to crank up the volume now and then?
What kind of amplifier do you have?
What kind of music will you be mainly listening too?
How large is your room?
Do you live with someone else that might object to their size?

If your like me and live in an apartment than a full range speaker makes little sense. Because if I want to turn up the volume the neighbors will complain (due to the bass). Even at lower volumes, full range loudspeakers can produce some serious low bass.

On the other hand, if you want to really feel the music, than a pair of horn loudspeaker (Klipsch) would be a good choice. Also they are easy to drive, so a low power tube amp can be used.
Magnepan LRS would be a great speaker if your not going to play them loud and have a smaller room but they need to be placed away from the walls. Great clarity but need more power.

Also remember to look into a good quality integrated amp or separate components. If you drive any of these speakers with a mediocre receiver than they will all sound unimpressive. 

I would recommend Klipsch RP-600 or even the RPM-160m. Based on your listening habits and room size. Clarity at low volumes and can crank if you need to. The RPM-160m is around $400. This would leave room for a decent sub and your all set. Klipsch has done a great job with these speakers, they punch above their price point. 

Op where are you located 

CrashmarsThis is a tough question to answer as you have not listed your amp nor source. Something like a Klipsch Heresy can be purchased used for your budget and rock the house with a flea watt ebay  amp. On the other hand,  some speakers, for instance some versions of Thiels are going to require many thousands of dollars in amplification. Location would help as someone with time and inclination might look on your local craigslist and make a recommendation.