The pressure compensation is is a small 1/2 npt plastic piece that looks much like a cgb but has a small hole for air flow on each side and a stuffing that only allows air flow in one direction (out). I may try the bubble wrap. I will climb up there in a few minutes and see about the packs...
I had to installed some IP bullet cameras in some PVC pipe on a Hopper dredge to protect it from the salt water spray. They are outdoor cameras but they are made out of aluminum and they will rust if left unprotected. I sealed them in the pvc and used a cgb from the wire as well as sealant on...