Have you looked at this one -
William Coupland death 1863 Dumfries Dumfries , born 1786(SP)
freeCEN website has a transcription for 1841
High St. Dumfries Dumfries'shire
William Copland 50 provision dealer
Agnes Copland 55
John Copland 20 hair dresser
Ages look to have been rounded down as per census instructions
http://www.freecen.org.uk/Looking at the index on SP for the 1861 census there is a William Coupland age 75 Dumfries Dumfries
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