Item Context on Sales Agreement

We are working on Oracle R12.2.6 and the Custom Item context created in Oracle Pricing are not available in the Item Context LOV while I am adding line to the Sales Agreement in the Order Management.

After adding a record in Item Cross Reference, the value is available in the LOV value but not behaving like the standard Item Context.

How can I have the custom Item Context to behave similar to the Standard Item Context like "Item Number"? So that When I add a line to the sales Agreement, corresponding record should get added to the pricelist associated to that agreement.