A throwaway printer is probably your best practical option.
Other than that, using a vintage dot-matrix printer with a low enough resolution (e.g. a 9-pin head) that it's unlikely to have either the smarts or the resolution needed to make this work.
Of course, this just means that if you are conspicuously buying a curated collection of vintage printers, you're providing another type of evidence.
Maybe you could 3D print a plate containing the document you want to print, raised and mirrored (like a printing press, but without movable type), and then ink the plate and press it onto a blank piece of paper.
EFF seems to think that all modern laser printers have some form of tracking dots, whether or not they've actually been able to detect them [1].
They don't say anything about inkjet, though. Unclear if this is because of a fundamental limitation of inkjet printers, lack of interest, or just because inkjet printers kind of suck compared to laser. :P
Buy a cheap printer with cash, from a location several hundred kilometers from you.
Go to a non-local Staples, FedEx, Kinkos with a USB stick, pay with cash for copies/printing. Better yet, pay someone else to do it for you.