[...] And to get those libraries, you're exposing the offline machine to website downloads, or even worse going online with it to get the backported libraries.
Not necessarily. One solution is using Synaptic offline, for example:
https://bitcointalk.org/index.php?topic=777625.0It's true, but I don't want to encourage people to do this at all, because of the circumstances. Even if a person was to follow good advice, the risk they could still end up with stolen coins or nuked wallets is too high (for me).
If this wasn't about money (or some other super-valuable data), I'd be telling people to be courageous and give it a try.