Yes, we have a certain stock of rubber boots / wellies at our visitors centre, from which you can borrow a pair free of any cost, but it might happen that your specific size has already been borrowed by another guest, hence we might suggest that you buy a pair of cheap ones at the river port in Leticia / Tabatinga, further after using them and if you do not want to carry them during the rest of your trip, just leave them at our visitors centre as a donation, handing them to one of our volunteers and instructing him to add them to our stock.