Thanks for the replies.

Australia.

The FAA turned around a faxed request for de-registration in one day.

My local FAA office says the FAA doesn't do Export C of A's for foreign
built aircraft. I suppose the buyer will have to settle for the
original German one or have a condition inspection done on arrival.

Still not sure whether the folks at the port will want to see anything
beyond copies of the bills of sale, titles, and (de-)registrations.

Jonathan