In the Orthodox churches here in Southern California, yes, and some of them like the Syriac Orthodox, the Assyrians, ROCOR and the Copts keep baskets of headscarves for women to use who show up without them. I'm not making this up; my mother has availed herself of this faculty on occasion and much appreciated it. Of course many of the young women wear them loosely for most of the service, and then tighten it up when approaching for Holy Communion, which I have to say I find a turn on. In fact these scarves in general, especially when worn in the Russian manner, are aesthetically pleasing, perhaps distractingly so, but only in the church. I would not want to live in a Muslim country and never see the hair of a woman who wasn't a member of my household.
For that matter, I believe the lovely hats English ladies traditionally wear to church, such as were seen in abundance at the last Roual a Wedding, are an acceptable head covering. Mandating headscarves is reading between the lines IMO. If so one turns up to an Orthodox parish dressed like Her Majesty Queen Elisabeth II when she is out of doors, with a suitably conservative and graceful hat, they are IMO appropriately dressed to receive the Eucharist. But that is my laymans opinion and it's for the bishop to make the call, and if the bishop mandates scarves then that's not a problem for me. But I do think our mission in the west could be aided by a "posh hat or scarf" policy. What I think we need to avoid is the impression that we force these things on our women, when it's an article of faith, and we don't want our society to be like the Islamic world, like Afghanistan where women are completely obscured and rendered almost helpless by the Burkha.