OK, now I see my error. The reference to Charles I should have made that clear, but I was careless (Halliwell himself did not offer a specific date, at least not in the edition of Popular Rhymes and Nursery Tales that I have).

I do realize that the verses I posted are not directly related to the Carrion Crow, hence my comment, but because Halliwell printed those verses directly after the text from the Sloane manuscript I posted them. He gave no commentary regarding the relationship between the two but - for what it's worth - the opening line "there was a crow sate on a stone" is fairly close in form to opening lines in many versions of Carrion Crow in which the crow (or some other bird) sits on a stone or log near someone thus beginning the narrative.