Old thread I know, but why not place another offcut of plastic inside armour to double thickness - like a small washer, then rivet would work as normal and strengthen fixing point!
I agree they are awesome skills and I admire anyone that takes it upon them self to create props from scratch, my comment was aimed at the idea of a production run - incase it got misconstrued!
I agree, I can understand somebody making their own as a challenge or for fun... But a lot of effort for a run of what we can almost definitely say be inaccurate versions!