Hard to not give a somewhat generic answer without the kind of ideas of things that need to be manufactured (and in which area).

Maybe try to find companies like Rtone (I'm not money related with them): https://rtone.fr/en/

Or go to fairs/shows for equivalent ideas of things, there is always those behind-the-scene workers around.

Honest intentions but hidden (private) knowledge.

Wishing you the best !