For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningRear Seat Back Cushion Cover and Pad Replacement - Left Side
Preliminary Procedure
Remove rear seat - left side. Refer to Rear Seat Replacement
Rear Seat Back Cushion Cover
Procedure
Remove the staples from the seat back cover.
Remove seat back cushion cover from Velcro.
Rear Seat Back Cushion Pad
Rear Seat Back Cushion Cover and Pad Re ...
Instrument Panel Upper Trim Pad Insert Replacement
Preliminary Procedure
Remove the instrument panel. Refer to Instrument Panel Assembly Replacement.
Instrument Panel Upper Trim Pad Insert Screw (Qty: 6)
Caution: Refer to Fastener Caution in the Preface section.
Tighten
2.5 N·m (22 lb in)
Instrument Panel Upper Trim Pad Insert Asse ...
Accident With or Without Air Bag Deployment - Component Inspections
Warning: Proper operation of the Supplemental Inflatable Restraint
(SIR) sensing system requires that any repairs to the vehicle
structure return the vehicle structure to the original production configuration.
Not properly repairing the vehicle structure could cause
non-deployment of the air b ...