In fact, the plastic mesh screen CAN be replaced without removing the front bumper, BUT, I'm not sure it is worth the effort to do it that way!
The two major obstacles, when replacing the grill with bumper in place, are the oil cooler and the (for want of the correct term) air guide to the radiator. If you chose to try it and not remove the bumper, you will need a long, thin box end wrench (13mm?) to remove the oil cooler mounting bracket. Leave the oil lines intact. The Air Guide will take some masterfull "wiggling" to get out and back in, but can be done with patience.
Of course, the under body tray(s) have to be removed first for access.
You will then need a long but very small, sharply pointed Phillips Head Screw Driver to remove the 18 (yes, count them!) screws that hold in the Grill. Again, patience, patience! And do buy some liniment to apply to your lower back after lying in a very contorted position for a very long time. Or perhaps you have the luxury of a lift! How lucky!
Yes, the price is in the < $100.00 range for the part.