PPAP Procurement

Dear Friends,

We have a Business Scenario where we Procure Items from Supplier for Quality Validation and then confirm it back to the suppliers(PPAP). These items are also procured normally from the supplier. Hence, in system, it is a common item only. We wanted to have a mechanism for differentiation of PPAP procurement, at the time of raising the PO as well as making the receipts. 

We thought of defining a new Purchase Order Line Type, but Purchase "Line Type" information is not visible at the time of making receipts. Also, we want  to ensure that the Material procured under PPAP is received in a particular sub inventory only. Now, the PPAP items are also procured through regular purchase cycle and hence, we can not set up the Default Sub Inventory for these parts.