https://infogalactic.com/info/M-DISC

Whether they will last 1,000 years as claimed… I’m sceptical, but even 10% of that will be enough for practical purposes.

If you use TOR, you will have anything touching your IP address on some government watchlist. Couldn’t tell you what form, but that stuff gets logged. Nothing likely to ever come of it, but it’s worth noting. The IP addresses of TOR nodes are essentially public information, and fairly easy for nation state actors to monitor. And the last hop to whatever site you’re connecting to is by necessity not encrypted the same as other TOR link traffic, unless you’re connecting to .onion sites or hidden services (which may or may not have their own issues – I haven’t been researching in the last few years). That’s not to say don’t use TOR – any latency minimizing anonymizing network is going to have similar issues.

Bitcoin isn’t a bad idea, as long as you keep in mind that you need to be able to consume real things in real life at some point. Which means that at the end of the day any exchanges that turn cryptocurrency into cash are your vulnerability. This is more of a nation-level adversary risk, but even big tech could cause problems by refusing transactions with cruptocurrency exchanges if there’s a real move to go to war against badthinkers (e.g. “OMG, the insurrection was funded with BTC – can you believe exchanges aren’t refusing to sell dollars for BTC from these extremists?!?”).