1840 double EL with boxed CORK / SHIP LETTER

1840 Entire Letter from Melbourne to London, landed in Cork and with a light but virtually complete strike of the boxed CORK / SHIP LETTER (F/K 443) in dark grey with matching CORK on the reverse, also with red Dublin transit "diamond" and London arrival.
The letter mentions enclosures, explaining why the original manuscript charge of "8" was doubled to "1/4".
Ex J.E. Foley collection.