Seedphrase Storage

So I've decided that I need to take the storage of my crypto up a notch. Up until now, I've been using a hot wallet + cold wallet system. Hot for more day to day usage and cold for my long term stuff, that very rarely sees any activity. This has been great so far but I want to take things to the next level if viable.

I've been looking into storing my seed phrase on an encrypted USB with the help of an airgapped device. The big question I have with this though is can I use an old device that is no longer being used and will never see an internet connection again, to act as the airgapped device to put my seed onto USB?

Any help or suggestions appreciated!