diff --git a/rattail_corepos/importing/corepos/db.py b/rattail_corepos/importing/corepos/db.py
index 0ff5ce5..63b6894 100644
--- a/rattail_corepos/importing/corepos/db.py
+++ b/rattail_corepos/importing/corepos/db.py
@@ -786,9 +786,12 @@ class ProductCostImporter(FromCOREPOS, corepos_importing.model.ProductCostImport
         self.products_by_item_id = self.cache_model(model.Product, key='item_id')
 
     def query(self):
+        corepos = self.app.get_corepos_handler()
+        op_model = corepos.get_model_office_op()
+
         query = super().query()
 
-        query = query.options(orm.joinedload(corepos.VendorItem.product))
+        query = query.options(orm.joinedload(op_model.VendorItem.product))
 
         return query