It looks like the red lens is facing forward in the picture. All red lights need to be facing the rear of the truck. (rear side marker lights can also be red) The orange/amber should be facing forward.
As to finding lenses....if you can find a number on the lens start regularly watching Ebay. My theory is that eventually you can find anything you need on ebay...you just have to be patient. You could also try
www.taillightking.com From when I have looked at the site he has a large and varied selection. I'm sure there are other sites as well but this is the one I know of.
Tad
