Lens boards are small plates that you fit a lens to, and then fit the plate and lens onto the camera.
Personally I just make new ones. While the Aluminum plate for my Model D was nice and fancy, I didn't actually have a lens that fit it. The lens I do have for it lives in a 'temporary' lens board I made out of layered cardstock, wood glue, and sharpie... I had only made it to test the camera a few years ago, and haven't bothered making a better one since.
As for photos, you can host them somewhere else and link to them, or try resizing down to like 800 on the long edge and uploading here.