Thanks for the responses guys. I did finally find mine, so they were there originally. All four were in the driver's side door bag, and I did the passenger's side first.

Part of the reason for the scratches on the original glass was I think from loose or broken parts. The passenger regulator was shot, and I know the glass was way loose. The driver's side slider (the big square metal part that bolts to the glass and hooks onto the rear track) was broken in two. That's why THAT side was loose and sloppy. It was originally spot welded together at the factory, and the spot welds were cold and just snapped at some point. I was able to join them together with a couple small machine screws and nuts. Now that this is bolted to the glass, there should be minimal stress on the screws, it should last forever. Also, the wear on these felt sliders indicates that they were put in crooked at the factory. I was able to wash and clean them up, and put them in straight, they seem to work as good or better than new.