hi we went to paros with kosmar a couple of years ago it is a lovely island . i have found a good site that will tell you which tour operator goes to any island if you search for gnto database uk tour operators you should find it just select paros and you should get a list of companies going there , it easy to get to if you book your own flights easyjet fly to athens or mykonos both of which have ferry links or fly to santorini and get a ferry if a company like xl can go bust there is know telling if any body else is much safer, at least easyjet are still making some money..