Surprisingly there are a few, fairly small for such a high resolution. 21.5" Cheapest brand 2560x1440 monitor that I recognized was $400.
[PCPartPicker part list](http://pcpartpicker.com/p/XT6gQ7) / [Price breakdown by merchant](http://pcpartpicker.com/p/XT6gQ7/by_merchant/)
Type|Item|Price
:----|:----|:----
**Monitor** | [Acer S220HQLAbd 21.5" Monitor](http://pcpartpicker.com/part/acer-monitor-etws0hpa01) | $99.99 @ Amazon
**Monitor** | [\*Hannspree HE225DPB 21.5" Monitor](http://pcpartpicker.com/part/hannspree-monitor-he225dpb) | $89.99 @ Newegg
**Monitor** | [Acer UM.WV6AA.A02 (V226HQL Abmd) 60Hz 21.5" Monitor](http://pcpartpicker.com/part/acer-monitor-umwv6aaa02) | $96.68 @ NCIX US
**Monitor** | [Acer K272HULbmiidp 60Hz 27.0"...