Have you ever seen a waterproof recessed can?

One of our builders wants to have can lights under a deck. The deck will have a dry-below type of system and they want the cans to shine through it. I can't think of any way to make this work, can you?

I put one in a few years ago in one of those Kohler sauna/shower units. Had to buy a six inch hole saw so I wouldn't ruin it. It came out great. I also scavanged one from a demo job. It's stainless with a big gasket to keep the moisture out. I'd bet the orange box even has them. They might even build a factory in China just make one.