I do not have any information beyond Matilda to determine her maiden name.
I have them listed in the 1880 Pender County Census. See: Census Place Union, Pender, North Carolina Family History Library Film 1254976 NA Film Number T9-0976 Page Number 542A
I went to the Hopewell Presbyterian Church and Mt Holly Baptist Church in July of 2007. I've seen some of the grave sites. The ones I saw with my own eyes and copied the information from their tombstone are identified below with an *. Other information came from census.
*James Piner b: 16 Feb 1833 d: 15 Aug 1887 * m: Matilda Piner b: 27 Mar 1835 d: 8 Apr 1928
I have some of the children you list, but not all. I have: Roseb: <1861> *Sydney R b: May 1866 d: Mar 1949 *m: Alice Anderson b: Feb 1864 d: Feb 1944 Georgeb:<1869> Marthab:<1875> K E?b:<1877> Addieb:<1877>
The only Newton I have seen a gravesite for is: *Maggie Newton Pinerb: 29 Feb 1895 d: 7 May 1981 She is buried in Cherry II 135 1, of Riverview Memorial Park on Hwy 117 outside of Wallace, NC.
I have a couple of Newtons in my GEDCOM. I just don't have much more room.
You may contact me direct at firstname.lastname@example.org