Can a dealer sell a car in the state of sc without the airbags in it?

No. There are federal regulations mandating that cars sold/traded in the US past a certain year must have seat belts and airbags. If you were sold a car(1993ish or higher) and it doesn't have an airbag then chances are the vehicle was totaled and repaired.

If the car was built before airbags were required by law, then the car can be sold without airbags.