I think you can buy just the springs, maybe $40 each.
I found the picture of the upper spring mount.
You have to remove at least three of the bolts so you can remove the upper shock mounting bolt. Then you can put both shocks on.
You could cut four spacers out of pipe or heavy wall pipe to fit between the plate and frame. You'll need longer bolts. The electrical suppy houses sell 1 5/8" x 1 5/8" 1/4" thick square washers in what ever hole size you need. Lowes and Home Depot should have them.
If your springs have rust pits I would buy new springs. I think that would solve your problem.
Dwight
