Field Monitor for 5D Mark II
Depends on what you want it for... there are framing, color reference and evaluation(scopes) monitors.
If you want lightweight and sharp and relatively inexpensive, with basic features such as peaking(focus assist) try the ikan VL5 round 225 could set you right heres one at B&H http://www.bhphotovideo.com/bnh/controller/home?O=&sku=895229&is=REG&Q=&A=details
If you need something larger(7in.) high rez with great color and more features i would suggest you check the ikan Vk7i or Vx7i
And if you need best of both worlds high resolution IPS pannel with great color and multiple scopes including waveform and Vectorscope...try the ikan D5w or D7w it wont be very cheap but it is...in perspective to the time it can save you from color correcting and re-shooting blurry footage.
here is a comparison chart that might help you find what you are looking for.
hope it helps:-)
Show what you see.