Netsuite在采购订单中添加行项目时检查库存项目供应商列表

I am trying to create a client side script that checks an inventory item is actually supplied by the vendor that was selected in the body field of a purchase order. I can get field values for the current line item but don't know how to load the list of vendors that have been tagged to supply that item. Alternately it would be nice just to have the list not show any item that is not available from the selected vendor. Any help with this would be greatly appreciated. I am trying to create a client side script that