Okay 5 more years and still no nearer the original.

Just one little flicker of light. In Dave Hillery's excellent thesis (online) he gives a version of the song recorded near Whitby. He gives the same unverified info re Blockley writing it in 1870, but here's the flicker of light, a proposed title 'Hooray for Dear old England and Her Flag that's waving in the Sky'. Somewhat long title even for a Parlour Song. Nothing on Levy, nothing in Kilgarriff. And nothing by Googling.

Where are those folksong sleuths when you need them?