x2 on the part # being on the shock body. And any half way decent parts house should be able to check availablity or cross over to thier brand. As far as that rear bracket goes that is definitly a major hack job and no it shouldn't be sitting at that much of an angle. As a matter of fact, from the looks of it, theres a good chance the bushing washer is coming in contact with the bracket. On that type of shock mount the frame bracket should be roughly parallel to the washers and only compress the bushings off angle a small amount when the suspension is working up and down. Hope that helps.
Dave
In taking another look at the rear pic it looks like the shock might be compressed most of the way as it sits which would limit travel if you hit a big bump and it trys to compress. Been to long time since I worked on a truck of that vintage, is it possible the other bracket thats above on the side of the frame is the original shock mount???
Last edited by DaveMcK38; 04/18/2020 3:19 AM.