when you look in quotes in the mishna, midrash, tosefta, braita and talmud - all works that can be dated to 3rd and 6th century...they are the same as today, more or less... -this is hearsay for me so please correct me if im wrong - the tefillin [phylacteries] that they found in the cumran caves and the texts of prophets that they found [dead sea scrolls] also indicated that it was the same
Mendy, there is a very interesting book titled
The Bible As Book: The Hebrew Bible and the Judaean Desert Discoveries - a series of related papers on the process of textual transmission and canonization in light of the DSS evidence. Almost without exception, the DSS material speaks (1) to a plurality of textual variants, with (2) a significant tendency to favor the non-Masoretic (e.g., Samaritan Pentateuch & Septuagint Vorlage) text, and (3) an absence of clear distinction/demarcation between so-called Canon and Apocrapha. Feel free to believe this or not. It
is, however, a fact.
As for the Masoretes, the laudable transcription abilities of 4th-6th century CE scribes says absolutely nothing about the textual plurality that aparently characterized Hebrew scripture up to and during the 2nd Temple period.