Grow your own sponges, washcloths, and scrubbers!
I have plenty of seeds from my first crop of loofa gourds. No guarantee although I did sprout some to make sure they were viable. Only seed from the straightest, most fibrous gourds have been saved. I can send 20 seeds or so in a regular envelope for $1 or make a trade for your heirloom vegetable or herb seeds.
Here's a site that explains how to grow, harvest and use loofa sponge.
www.luffa.info