The young Thai coconuts that I've seen at WF and other markets have had the husks removed and have been dipped in spoilage retardant, then wrapped in plastic wrap. They stay "fresh" for a long time.
I've seen untreated young coconuts for sale online, but the shipping cost is very high. Google "organic thai coconut" and see what you come up with.
My preference is to order products from Tropical Traditions. I get their flaked coconut, and sometimes their coconut cream or coconut oil.
I know this is not exactly what you are looking for, and I wish there were a better alternative. When I was very young and lived for a while in a coconut-growing country, I loved getting young coconut from vendors with machetes. First, they'd whack the top off the coconut and we'd drink the water from a straw. Then, we'd hand the coconut back to the machete guy, and he'd whack again, cutting the coconut in half. We'd scrape out the young flesh with a wedge of coconut husk. Oh, my! So good!