The shock is just missing the top rubber bushing, a washer, and the nut. Should be able to pick them up at any automotive parts place.
It looks from the first picture that the face frame is not perpendicular to the slide or RV wall. That shouldn't have been a problem but the the nylon skid is loose. By looking at the picture, I'm guessing that it went out 1/4 inch too far or the nylon skid was too far in. It looks like your slide has slid out past the nylon skid plate but it could be that since the screws were broken, the slide pulled the nylon skid plate in then slid past it when you put it back out. Also, That grove in the nylon may be caused by the head of a broken screw or a screw protruding from the bottom of the slide which could also be what broke the screws to begin with.
The nylon skid will need to be re-attached before you bring the slide in. You'll have to raise the slide floor first. It's not real heavy. If you have someone to help, he or she can push the nylon under while you pry the slide floor up.
If not, a spring board on either side about 6" from the RV wall will lift it and fall away as you run it in. If you aren't mechanically inclined, a spring board for that job would be a 4 or 6" board about 1/4 to 3/8" longer than the height of the slide floor. You can also shim under it to make it long enough. Put it where you want it under the slide and pull it vertical which will raise the slide a bit. Make sure the flat side of the board is facing the RV and it will fall away as you run the slide in.
The face frame around the slide is all that holds the slide in the RV so once you have it in a bit you may need to tighten the screws or add 1 or 2 more to keep the face frame perpendicular and tight.