Maybe your best option is to buy some here. Lost's of shops carry mask, snorkel and fins and you can support a local shop. There is a shop (Walmart packed into about 200sq meter) just inside the plaza behind the Downtown HiLo AKA Value Master. He had mask and fin's and the last time I looked at them it wasn't a bad price. At the end of your trip give them to a floatie vendor. Capt. Chris is just starting up business and he would love to see you. Capt. Chris is at Sun Beach.