The document you quote (incorrectly) is known as the "Hazard Circular." It's usually credited to London bankers, not northern ones. Sometimes it turns up in antisemitic rants, making the connection between the European banks and the Rothschilds. In any case, it's provenance is not much better than the Protocols of the Elders of Zion.
It looks like you cut and pasted it out of the League of the South's site, since the error and attribution are identical.
You are quite correct as to the origin of the quote. My point was that the North was concerned with labor just as the South was but in different ways. Moral objection to slavery wasn't a Northern banner.