Hi
Just a few suggestions you might already have come across
Try Glenavyhistory.com it covers Killead and is a very good website, the following comes straight from that site
The following names can be found today on the headstones in the grounds of this church: (Preb. Church)
McCraight
Robb
Robb, Straidhavern
Robb, Tully
Robertson, Ballygomartin
Also the 1851 Census is worth a look at as Killead is one of the few areas were records from 1851 still exist, just google 1851 Census Killead
I tired to get access to Chuch of Ireland records for Killead but I was told that the Orginals are now in PRONI.
yours
Magheragall