Norton, Mass. was created in 1710. So both Sylvanus and Mary must have been born (and married) elsewhere. That said, I just looked at the published vital records for this town*, and they do record some earlier dates, including (under spelling of CAMBELL):
Rachell, ch. Selvanis and Mary, Jan. 31, 1692 or 3 <-- despite this early birth record, there is no marriage record in the Norton VR for Sylvanus and Mary.
Deborah, ch Selvanis and mary, July 17, 1694
Mary, ch Selvanis and Mary, May 8, 1696
Abiah, ch. Selvanis and Mary, Nov 22, 1697
Sarei, ch Selvanis and Mary, feb 27, 1698/9
Selvanis, ch Selvanis and Mary, Oct 19, 1701 [ck]
Ruth, ch Selvanis and Mary, mar 26, 1703
Gershom, ch Selvanis and Mary, Nov 14, 1704
Neomi, ch Selvanis nd Mary, Feb. 9, 1705 or 6
Abigaill, ch Selvanis and Mary, Oct 10, 1707
William, ch Selvanis and Mary, Jan 1, 1709 or 10
Caleb, ch Selvanis and Mary, Apr 13, 1711
Ruth ch Selvanisi and Mary, Apr 9, 1714
Jeremiah, ch Selvanis and Mary, feb 17, 1715/6
Mary, wife of Salvenas, d. Feb. 13, 1723-4
I do not find a death of Sylvanus Campbell in Norton.
Norton was formed out of Taunton, MA, so maybe they're there...
I'll go see what I can find.
*
Vital records of Norton, Massachusetts, to the year 1850.