Tech Instrumentation has a great selection of non contact IR thermometers to choose from. 

The main factor in the difference in price is the optical resolution, which is shown as a ratio - 6:1 for instance.  This tells you how close you must be to the object you're measuring.  A ration of 6:1 means that the spot size of the surface you're measuring will be 1" in diameter at 6" from the target.  The diameter will be 2" at 12 inches from the target, 3" at 18" distance and so forth.  Feel free to give us a call or send us a message if you need a more in depth understanding.

Please click on the image for more details regarding each item.