I have two Elfreths, both from NJ.
Elizabeth Elfreth, no dates, m. Isaac Andrews in 1738;
and
Mary Elfreth b. 1781 m. Samuel Allen in 1809 in NJ
Mary's parents Jeremiah Elfreth and Mary Roberts; Mary Roberts Elfreth later married William Taylor.
I have descendents of these marriages; contact me via my e mail address if you want further info, please.