CAI did assemble garands from parts and a cast receiver and charge around $400 for the rifle about 5 or 6 years ago. Unfortunately many of these rifles were very problematic as the receivers were made out of spec with poor quality control- kind of par for the course with Century assembled semiautos. They are generally considered to be worth the sum of their parts ninus receiver- approximately $200.
If you buy an M1 make sure the receiver says Winchester, springfield, HRA, or international harvster on its heel.