You can easily keep Wikipedia around - burn it on archive BDs(M-Disc), they are easily hidden, can take the whole Wikipedia in one disk and basic information is extremely valuable in an oppressive regime. Then do the same for a collection of E-Books based on what is most likely to be banned/what the right wing does take the biggest offence on. And what aids you the most in either getting out or resist.

Using archive BDs(M-Discs) is important as regular storage devices can easily be detected due to their metallic contents and they degrade within years. M-Discs are far more resilient and can be almost as easily hidden.