Solution : https://service.sap.com/sap/support/notes/506239 (SAP Service marketplace login required)
Key words : 
special procurement key 'direct procurement', create production orders, configured sales orders, individual customer segment, read master data, direct procurement, master data, -inventory-managed, -stock components, manually insert
Related Notes : 
       
| 538512 | Direct procurement for reservations for KMATs | 
| 488151 | |
| 409619 | |
| 353217 |