Hiya John, the aquarolls that I filed out where from the '80s, so I would think they are about the same age as the ones that use.
The water carrier that I filed out would be from about the late 90's I would think, don't hold me to the dates tho', I may be out by a couple of years, but they aren't too far out. The plastic around the screw threads is good and thick and the cap is only there to seal it when moving it or when awaiting to be used when swapping over so I find that it's enough.