There are plenty of people who "got saved" after one single solitary sermon and NEVER possessed the entire Bible as we do today.
Including probably the majority of the early gentile Church. Did these gentiles own every OT scroll? EVER? Not a chance.
Act 13:48
And when the Gentiles heard this, they were glad, and glorified the word of the Lord: and as many as were ordained to eternal life believed.
And I recall the various accounts of how blind and deaf persons had only ONE of the gospels available in braille. That's it and that's all.