I think the system Hollow Earth Expedition might fit the bill. Not sure if they have adventures for the system, but the setting information could be inspiring.
For other inspiration, maybe take a look at movies like the Rocketeer?
You could also maybe re-theme adventures to replace magic or supernatural elements to be "weird science." Instead of summoning Cthulhu, maybe the cult is instead some group of mad scientists making a death ray?
Just an idea.