There is no place I know of to purchase Levo online w/o a prescription, though you may be able to contact a doctor in the country you are currently residing and get a script.
You should always make sure you have enough medication to last a while, when traveling, especially abroad; or at least plan ahead on how you will obtain your next prescription.
Do you usually have a prescription? You could have your prescribing physician fax your prescription to a local doctor.