I have Stanley spring close by prob have them re arched when they are out. Both cars had air shocks, cant imagine why!
I worked in a spring shop for 14 years. I made springs as part of my job. Your springs won't hold the rearch without adding a extra leaf or replacing the #2 leaf. (the main leaf is #1, the next one is #2, the next one is #3, .....).
When I made new rear springs for my charger I made all new leaves but reused the bottom leaf. I arched the bottom leaf to fit the new pack. I reused the bottom leaves because that is the leaf with the mopar #'s stamped in it.
If you go through the work and expense to rearch what you have without replacing or adding a leaf, you wont be happy because it will sag back down to where it sits now.
As for the broken leaf, Thats just part of being a leaf spring. Leaves break. Usually after a harsh shock. Almost never under a heavy load because under a heave load the spring is under constant floating motion through its travel. Under low load a harsh shock jars it and cracks it. On old springs a lot of times you will find stress cracks in each leaf when disassembeled. If they are stress cracked do not reuse them. They will break. Also heavy rust between the leaves will cause them to break.
Its also not a good idea to reuse u-bolts. They stretch when torqued, the nuts might come off but when reused the nut will likely only tighten down to its previously tightened position. if that position isn't tight enough your spring will break at the center bolt hole (The weakest point of the spring do to the hole drilled through it). If you ever have a broken spring between the u-bolts, the bolts were not tight enough.
