First, the only dogma of the Orthodox Church regarding Mary is that she is the Theotokos (One who bore God), the Mother of God.
Second, the Church does teach, proclaim and affirm that the belief in her Ever-Virginity is an unbroken belief held by the Church since the beginning.
The Church reminds us, further that "it was the practice for devout Jews in the ancient world to refrain from sexual activity following any great manifestation of the Holy Spirit." (Ibid)
Regarding St. Jospeh, GOARCH says
The Lenten Liturgies are full of that ever-held belief
"Who would not call you blessed, most holy Virgin? Who would not praise the painless birthgiving? For He who shone forth from the Father as only-begotten Son, the same now came forth from you, taking flesh in a manner beyond describing. Though God by nature, for our sakes He became man by nature, yet not split into a duality of persons, but revealed without confusion in two natures."
"O novel wonder and befitting God! * for the Lord himself has manifestly traversed * the gate of the Virgin, which was shut. * Raw God in His entry, * in His emergence He appeared as One bearing flesh, * the gate remaining shut notwithstanding. * She is unutterably God's Mother, and her we magnify." [Sunday Orthoros, III Mode]
"Lord, even as You came out of the sepulcher, though it was sealed shut, likewise You entered where Your Disciples were, the doors being shut also." [Sunday Orthodox, Plagal Mode of the 1st]
My contention, kosta, is simply that these things cannot be affirmed in scripture. That's the point, and that is the only point.
They can be affirmed by scripture + something else.
I would argue that the perpetual virginity cannot then be 2000 years old. There were no church fathers writing approximately one decade after the birth of Christ. The only ones writing were those who recorded instances during Christ's ministry on earth, approx 3 decades later.
Since there is no clear presentation of any perpetual virginity in scripture, the best you can say is that the perpetual virginity was taught from about 18 or 19 hundred years ago.