Karl Dallas (100 Songs of Toil, 1974, 227-8) refers to the coal strike of 1844, during which blacklegs were brought to Tyneside from Wales, Ireland and Cornwall and violence ensued; but that is not a dating of the song (though it seems that many people have assumed that it was) so much as an illustration, I think. It may perhaps be from that time, but we don't have evidence; and strike-breaking was common enough.

It's interesting to hear that the song was generally known. Was that mainly among children, or more general? Bert Lloyd seems to have been inclined to take credit for its circulation in the years following the first edition of Come All Ye Bold Miners. I daresay he was unaware of currency in "street" culture, though.