Resellers, imports, and tampering?

I’m planning to purchase a Pioneer from Mouser Electronics (as opposed to Olimex directly, due to the shipping/refund/currency fiasco I posted about previously), but they couldn’t answer the questions I had about product integrity. Can anyone here tell me what precautions, if any, are taken to prevent or show tampering by third parties? (Frankly, I wouldn’t put it past the U.S. to proactively alter, modify, or inject each FreedomBox that crosses the border.)

Perhaps the broader question (one which I’m really not equipped to discuss) is how to check suspicious hardware without contaminating a trusted system – or better yet, how to create a trusted system to begin with, and safely migrate one’s data to it.

But, if we figure (say, via at-home testing with guidance from users here), that a given Pioneer is “safe enough”, then my question becomes: Would its hardware also be suitable for use as a small desktop PC, to form the basis of said trusted system? In that case, I might want to buy two.

I tried with Debian (with LXDE) and with Parabola (with fvwm, no desktop environment).

The environment looks fine and you cand do things. Sylpheed works fine for email. For XMPP, profanity (command line) is ok, other things not great.

Loading even a rather light web page with Firefox (or any similar web browser) can take 100% CPU for 10 to 20s, so if you expect to use that kind of web browser, my answer is no. Epiphany is not better. If you are happy with dillo, this works ok.

If you tell me what software from Debian free repository you want to use, I can try it (I will not install anything not from Debian free repository, that includes anything from third party repositories for which Debian includes installers).

Based on your experience of Firefox, it looks like I’ll need something stronger, then.

I’m still hoping for answers about resellers, imports, and tampering, if anybody has recommendations about that. (Sure, maybe there are security how-to’s out there, but how does one find what one doesn’t even know the terminology for?)