... I do not plan to sell or use it. Is there a way to move it offline, either by printing something, a card, or something else that would make it super super secure (provided the physical info is in a safe place)...
Back to OP, for cost effectiveness I wouldn't recommend a hardware wallet. Yes they are great, but they are great for regular user interaction, for people needing a secure way to spend your funds without exposing keys/passwords. This is not the case the OP is asking, he/she wants a way to store keys and deposit funds only.
Once a wallet has been created and the Private key backed up somewhere (using any of the methods suggested by other users) he/she will only need the address to keep sending funds to that wallet and increase the balance. Online exchanges and merchants usually have an address book feature to make repeat payments.
A hardware wallet in this case is an unnecessary expense (they're not cheap). An encrypted container on a USB stick would serve the same purpose on a $5 USB drive, keys stored on the drive, address kept in the address book of where ever you'r buying them from, (I assume an online wallet/exchange).