We have a selection of Tommy Bahama beach chairs with backpack straps ideal for biking or walking to the beach.
These are pretty good models. We have six on hand (last I checked) along with two umbrellas
You can also bring your own or order them and have them shipped directly to the island.
Here are my recommended items – I own these and endorse them. If these end up at the house we probably keep them for your visit next year.
I bought a Sport-Brella XL and chair for $99 on a special direct from the Sport-Brella company.