In my opinion you can follow "Non-valuated sales order costing" method.
Please check the following link
Special Case: Nonvaluated Sales Order Stock - Cost Object Controlling (CO-PC-OBJ) - SAP Library
In my opinion you can follow "Non-valuated sales order costing" method.
Please check the following link
Special Case: Nonvaluated Sales Order Stock - Cost Object Controlling (CO-PC-OBJ) - SAP Library