It's not hard. More the equipment needed. assuming the compressor seized and didn't introduce any contaminants to the system:
You'll need an evac/recharge machine with leak testing capability
You'll want to evacuate the system, replace the compressor, replace the drier, replace the orifice tube, add oil to the system appropriate to what came out and the parts you are replacing, pull a vacuum for 30-45 mins to dry the system, leak check it for 30 minutes, then install a measured amount of refrigerant to the quantity specified