A cousin in Canada kindly supplied these images of two photographs produced by J. R. SAWYER, probably at his Ipswich studio, since our relatives lived in Suffolk.
Number 17,583A has been named as farmer Thomas HYEM (c.1801-1885) of Felixstowe, who married Hannah Maria BUGG (c.1815-1850) in 1839. The identity of the man in number 17,051B is not known. He looks about 50 years old, so he could be Hannah's brother, Charles Joseph BUGG of Boulge and Melton (c.1816-1908).
On the basis of the newspaper advertisements outlined in my previous posting, I believe these prints date from late 1866 or early 1867. I wonder whether numbers in the 16,000s had been assigned to negatives at Ipswich or Norwich.