Wayfair.com has a pretty nice-looking raised bed for sale. With a little bit of modification, it can also be used for a shelter for an on-the-ground tortoise:
https://www.wayfair.com/outdoor/pdp...dar-raised-garden-xql1109.html?source=gateway
https://www.wayfair.com/outdoor/pdp...dar-raised-garden-xql1109.html?source=gateway