We bought ours at Costco several years ago. Then I went to a dive shop & they put a prescription in my mask. We always take our own equipment. You could get away with using vendors fins depending on your foot size or where you are going to. Our recent South Pacific cruise most vendors requested you bring your own gear. We bring our fins too as my husband has large feet & no one carries over a size 12 that we’ve ever found.
Just to add we’ve used our Costco equipment many, many times & no issue. Since you’re not sure if you will snorkel again I would not buy expensive mask/snorkel.