What are the parts that you are missing?
Are they something that can be made by hand? In the past I've had to make lost parts, in most cases it isn't that hard and with armor they can sometimes be covered with cammo, mud, and such. In most cases people will never notice. We had to do this kind of thing all the time back before resin replacements and P.E.
Just yesterday I had a box of spare parts fall and eventually I used a large sticky roller on a mop sized handle to catch parts that I didn't see. I would roll it all over the floor and pick off the parts. Also check shelves, tops of containers and things to see if they landed there or inside a box. It couldn't hurt.