Zero passages say sola Scriptura
...it is like finding the right to an abortion in the Constitution...
That comparison is beneath you.
There are multiple passages that indicate we should use scripture to guard against false teachings.
My point on finding a right to abortion in the Constitution is, I think, valid. If you NEED the right to an abortion, then you can craft an argument about privacy and from that derive a right to an abortion.
And if you NEED for Mary to be sinless and a perpetual virgin, then you can take a sentence in Luke and call the references to the brothers and sisters of Jesus as referring to cousins, and you have what you need.
However, no one just reading the Constitution would think it had anything to say about abortion, and no one picking up a Bible and reading it would think Jesus was Mary’s only son, or that she was born & lived without sin.
This isn’t an area I get very emotional about. I think one of the serious mistakes made by many early church fathers was to spend too much time arguing over things not discussed in Scripture. You don’t need a perfect understanding of the Trinity to be a Christian - I hope!
So it is with Mary. If you pick up a Bible and read it without prejudice, you won’t derive Catholic teachings about Mary - you’ll get the contrary. However, if you CHOOSE to believe Catholic teaching about Mary, go ahead. As long as folks understand she isn’t God, that she isn’t our mediator, and that we shouldn’t ask her to grant our prayers, then I don’t care about the rest.