There's a waterproof soak for fleece clothing, there's Nikwax water-based softshell proof, mess of stuff out there in the outdoor stores.
I'd still have a hard time watching a good set of mics get wet.
The bodies should be sealed at the seams with clear RTV silicone sealant as well.
A roofer once told me "water has a way" meaning that it will get into anything it possibly can.
It drips in, capillaries up, soaks in, accumulates just from condensation, it has a mind of it's own.