If you are North american, you can buy great korean ips monitors on relatively cheap with 14-days return policy.
Check the Yamakasi Catleap.http://www.ipsledmonitors.com/Yamakasi-Catleap-Q270SE-Monitor-p/yam1.htmhttp://www.ipsledmonitors.com/Yamakasi-Catleap-Q270SE-Monitor-p/yam2.htmhttp://www.ipsledmonitors.com/Yamakasi-Catleap-Q271-Monitor-p/yam3.htm
Otherwise you can still but korean monitors on e-bay, mind the custom taxes though.http://www.ebay.com/itm/Ultimate-Perfect-Pixel-Crossover-2795QHD-AHIPS-LED-27-Monitor-2560-x-1440-DVI-D-/141577457012?pt=LH_DefaultDomain_3&hash=item20f6ac8d74
If you cannot / don't want to buy a korean monitor.
A bit higher than you budget, the best choice if you have an AMD GPU supporting Freesync: https://pcpartpicker.com/part/asus-monitor-mg279q
Otherwise, the best choice is this: https://pcpartpicker.com/part/lg-monitor-27mb85rb
All of the above are flicker free, have great color presets and contrast, have great responce times and are delay free.