Supplier Part Number

Client is into trucking business and has a requirement to map their item number to multiple supplier part numbers. Their current ERP supports this one to many part number relationship. An example of this is, they purchase vests from their suppliers in different colors or sizes. Each size or color has a different supplier part no. but to them its all one item i.e., vests. During PO receipt, they mix all of the purchased variants of vests into one bag to fulfill their customer requirement. We are wondering how to address this requirement in EBS, R12.2.14. The client also doesn't