Let me see if I get this clearly, you will only accept the original writings from Paul's own hand to which he autographs it as "authentic"??? No, YOU would be laughed out of a court of believers of the first century. They at least accepted what was personally sent to them by Apostles or their close disciples and did not question their authenticity because not only did they KNOW the authors, they KNEW IN THEIR HEARTS that they were receiving the truth from God. It spoke to their spirit, as from God.
What you seem to earnestly want us to believe, that it was "Catholic" tradition that made them authentic, cannot be based upon the facts. When the believers in Ephesus were hand delivered their letter from the Apostle Paul, for example, they had NO problem with its credibility, nor did they have reason to doubt its authenticity. The reason we don't have that "original" today should be obvious for a number of reasons, least of which is the false worship as a "holy relic" something like that would have received. God knew what he was doing.
Do I believe those Scriptures by faith? Of course, just as I do the fact that Jesus Christ is the Son of God, that he died, was buried and rose again for our sins, and that he will come again in glory. Where we differ, I think, is you base your faith on your Church, who tells you what you should believe. I prefer the more direct way.
BB, just the fact we have the canon of scriptures, preserved, I believe even Luther gave the Church credit for that.