My neighbor is a hammock (hamaca) weaver and has been short of material so we went to Manzanillo a few days ago thinking we could get better prices. It turns out we can buy this cotton (algodon) just as cheap here in Melaque. We definately need to find a wholesale source in the future because we are looking at $1000 pesos per large hammock with these prices just for material.
He learned his trade both in the Yucatan and Oaxaca and hope to find a better source. The past hammocks he's made are of Olefin Synthetic which is what they make large boat/ship ropes with. That will be even harder to find than a wholesale outlet. They sometimes make 'topes' out of Olefin Synthetic Rope, at least along the coast.