I was able to restore an old door, and build a new one at the same time!
In this case, I took sliding door hardware off our old sheep barn, and then built a new door out of some Western Red Cedar I had kicking around. Married together, the new door works well and compliments our new half-bathroom well.
The old sliding door has some history too. I am not sure when it was installed, but I have a photo of the old sheep shed from 1966 and it is on the building. The building itself was moved about that year from another part of our farm about a half mile away. I tried to move the sheep barn again three years ago, but I had wayyyyy to much bulldozer and not a strong enough building to hold up to said bulldozer, so it did not make the trip. If it had, it would have been a 100 year old building that had been moved twice; serving the barn in three locations.