Reading the Koha manual, the only fields available for the MarcFieldsToOrder are: price, quantity, budget_code, discount, sort1, and sort2. However, if a vendor is able to map additional fields, such as item type to the 942 $c, that should be made available.
Bug 34645 - Add missing fields to MarcItemFieldsToOrder system preference added some more fields, but they are all item or oder line level. So far it doesn't seem possible to map fields in the record.