Yes.
Sales order + SO lineNo is key. If it is same everytime specific customer orders , you can copy Order BOM of previos sales order from same customer. It reduces the data entry pain.
There is also option to copy material BOM & make changes in CS61/CS62.
There is also UI to copy Multilevel BOM using CSKB. System copies whole multilevel Material BOM to Sales order BOM.Each level is stored in Table.
CS14 has option to compare(multi level) SO BOM & Material BOM to check changes made are correct.
Hope it helps,
Jatin