@crinolinerobot This headstone is about three rows back, and the cemetery volunteers helped me track it down in the context of this ghost sign. The sign is located just a short distance from the High St entrance to Abney Park, and was where Robert Ellis and his wife lived and ran their ironmongers business.
I wrote a little about it here: https://cemeteryclub.wordpress.com/2013/11/14/ghostsigns-gravestones-and-the-painted-history-on-our-walls/
Streetview (with cemetery visible in the background): 10 A10
https://maps.app.goo.gl/idCWf9HvxmR9z8eB6?g_st=ac