No Prep Module: Criminal Caravan (Patreon)

https://www.kassoon.com/dnd/adventure/no-prep-module-criminal-caravan/ 

The Cult of the Glittering Thieves secretly hires the PCs to guard a caravan transporting stolen goods.  They operate outside the kingdom, transporting goods to fence in other  cities to avoid being caught. To everyone else, they're a legitimate  merchant caravan that buys and sells goods, but to a select few they're  notorious bandits, hiding their elicit activities under the guise of  random misfortune.