Excellence, to whom are you referring when you say “They did not stand at Har Sinai. We did.”? Non-orthodox Jews? If so, when a non-orthodox Jew becomes a BT, does he or she retroactively stand at Har Sinai?
On the original topic, when I lived OOT, there was just one seforim store. The owners were frum. They sold women’s taleisim — I remember seeing one that had the 4 imahos on the 4 corners. I think they also sold conservative and reform prayer books. I don’t know from whom they got a heter.