An interesting work, but do you really consider 1830 "of the period?"
James Madison, the last surviving Framer, was still alive in 1830. Numerous other Framers passed away in the ten years prior - John Lansing in 1829, William Few in 1828, Rufus King in 1827, Luther Martin in 1826, Charles Cotesworth Pinckney in 1825...
I would think that when you can go call on and talk to the people who were directly involved in, and indeed, the architects of, the event in question you can consider that "of the period."
Yes. Rawles was a teenager during the Revolutionary War, and "came of age" during the time frame when the Constitution was forumulated. He practiced law and was a high judiciary official (I forget which office he occupied), so his views are precisely "of the period".