I don't think it is common yet to be able to buy crypto coins/tokens yet, although we did do it for the VIVA ICO. We accepted wire transfers. I would say, wait and see what is announced via the email newsletter. But if you want to be prepared for the most likely case of having to use crypto, then buy some Bitcoin which can easily be turned into Bitshares if they decide to use that as the currency to buy EOS. Bitshares was Dan's first project and some say it may be the currency to buy EOS but really, no one knows, or at least I don't know! :-)