I have found that laser Range finders are practically useless for long range prairie dog shooting. If the dog is sitting on a mound and the grass is short you might have a chance. You will have to give up a lot of shooting when the dogs are feeding out in the grass on a flat prairie.
The best solution I have found is one of the WW2 optical range finders, such as:
The 12 power optic allows you to range prairie dogs sitting in the grass out to 1200 yards with ease. Gets a little tougher after that. Sitting on a mound would be even farther.
The one I just bought from SAMCO was in great shape considering that it was made in 1947 and had been sitting in a warehouse for all these years. There was some green funk on the brass buckles and leather harness but it cleaned up with a little vinegar and a soft brush.