I don't think any of the New Testament is derived from first century documents or is an original.
Well, according to anyone who's ever done intensive work on the NT - be they Christian, Jewish, agnostic or what have you - all the NT documents except two absolutely date from the 1st century, and there is a good chance that the remaining two do date from the 1st century as well.
In addition to this unanimous scholarly opinion, there is the fact that early 2nd century writers (100-125 AD) reference the NT documents as if they were already well-known and established documents. Additionally there are substantial manuscripts of the NT existing from about the year 200 AD and fragments from before 125 AD, including a possible fragment from before 68 AD.
So the facts contradict you.
You would be in the extreme minority on your view. Even most secular scholars who do not believe the NT holds any divine significance agree that most all the books of the NT were written in the 1st century.
I'm no Bible expert but I think the Letters of Paul are from the 1st Century.