You can find the Priest Outift in the Cabin in the Central Mountains. Below is the location of the Cabin. Inside the Cabin you will find a Skeleton and under his legs is the outfit.

The Leg Lamp Blueprint can be found on the East side of the map in a small wooden Cabin. Once inside the cabin you will want to break the wood which leads you down into the basement. Here you will find the Leg Lamp Blueprint - its dark, be sure your torch has batteries!