Hasbro/WoTC/TSR need to have module packs.
This is a pack of 6 mini's the go with the theme of a module.
I know it would increase the cost of a modules, but you could use the Minis for other games.
Make on of the Minis a 'Boss' Mini. They don't have to be high quality. Let the people buying the modules know whats in the package.. Also sell individual mini boxes themed to the modules set. Those you can keep the standard "We're not going to tell whats in it because 1 out of every 144 boxes has something rare." theme going.