Just found this on Amazon. If you use TAILS on a USB stick, it's just one more layer of added security. Keep your persistence folder stored on this one ;)
https://www.amazon.com/Special-Cryptex-Flash-Drive-Cool/dp/B0106QX9HI1
Edit: Several users here have pointed out that this would be useless against LE if you were busted. I understand this and it is being suggested merely as a deterrant to help keep friends and family out of your sensitives, nothing more.
Neat idea but if I was a young, enthusiastic LEO I'd just sit with it for a few days and try all the combos.