I need cactus fibers (looking to trade)

As the title says, I need cactus fibers to complete a quest, and I cannot for the life of me recall which islet I visited for them. I've used up several days' worth of fuel for voyages, and I'm turning to Reddit.

I'm on the EU server and would be looking to buy 4x cactus fibers through the island trading rack system. I have goods to trade in return for them : D (Tree Sap, Cash, uhh idk let me know if you need anything and I'll let you know if I have it)

Thank you in advance for checking out this post.

(I know this is a data-wipe beta and ultimately my progression doesn't matter, but I still want to enjoy my time and progress whilst I can) >.>