Why? Write it down. Perhaps leave multiple paper copies around with some trusted people, like your lawyer and a safe deposit box at your bank.
Your proposed device seems a bit complicated. You can get pretty far with a piece of paper and this protocol:
Construct your password from two parts. (1) random gibberish you write down on paper, (2) a 'correct horse battery staple'-style part that you memorise.
Btw, have you looked into Yubikeys? They are better than password storage, because they can store your private keys and do signing with them. The key never leaves the device. (They can also store passwords, I think.)
