Need Enhancement Spot or BADI for transaction ck51n

Hi,

The calculation of the sales order standard costs is done by only one type of standard cost in SAP standard while creating a sales order. I am trying to enhance that to accept 3 to 6 types of standard cost.

I need information of Badi or enhancement spot for transaction ck51n to implement the same.

Thanks in advance.

Regards

Shanthi