Thanks to all. As a matter of interest, the posting by Whiteout7 suggests Martin of Upton Grey, which is, in fact, the same line as Martin of Lockynge. Descendants of Sir Henry Martin, first Baronet, of Lockynge bought the house at Upton Grey Nr. Odiham.
I've discovered some tiny hallmarks on the back of the cufflinks. I plan to take them to a local jeweller to ask if they can get a date range as this would help pinpoint who had them made. Although we think they came from my husband's grandfather, they could be older than that.