For now it might be wise to email your bank, or even better if you can go in personally, or call them up.  Discuss with them about how to invoke your VISA card guarantee, which ensures that under a certain amount (I think it's something like £10k in the UK so it's definitely covering you here), under that amount if you can demonstrate you were defrauded they will return your money immediately and start investigating that website or company.

Get that ball rolling now, and if it turns out to be wrong you have lost nothing and gained back your coin value