It is officially added on Tibia Wiki that it is looted from Ratmiral Blackwhiskers same as other items from Jungle set.
According to the tibia fandom it is part of the Jungle Set, (not sold by NPCs) and this item so far is not dropped from any creature. By my research no one so far knows who to drop or the evidence of dropping the item.
Makeshift Boots - TibiaWiki - Quests, Items, Spells, and more (fandom.com)
Loqhakk - Applying to TibiaQA team as ModeratorJuly 26, 2024
Nareull - Applying to TibiaQA team as ModeratorJuly 14, 2024
Looking for new TibiaQA staff membersJuly 12, 2024