Just found this entry in the IGI which suggests that this John Costain died in 1853. However, there are lots of examples of deaths in the IGI which are ficticious.

JOHN COSTEAN Pedigree
Male

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Event(s):
Birth:
Christening: 21 APR 1850 Arbory, Isle Of Man, England

Death: 21 MAR 1853

Burial:

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Parents:
Father: JOHN COSTEAN Family
Mother: ANNE DUKE

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Messages:
Extracted birth or christening record for the locality listed in the record. The source records are usually arranged chronologically by the birth or christening date.