67 dart rear leaf springs help

hello again everyone
well i was looking at the rear suspension setup the other day after i ordered my shocks. i noticed that the rear leafs are looking more like a sine wave than a nice semi-elliptical shape. not a good thing i'd imagine.

so i am on the hunt for some new leaf springs. jc whitney has some but according to their literature, they are not for a 67 dart. but someone told me all darts/valiants a-bodies used the same leafs? their springs are $125 per side and free shipping. also found some on ebay for 189 plus shipping so roughly the same cost total.

now a really dumb question: i have a skeleton of a 53 dodge pilothouse pickup that i replaced the shackles and bushings on and the leaf springs on that are all good. i know it's a long shot but would any of those parts - leafs, shackles, u bolts, or bushings - retrofit to the 67 dart gt?

thanks again for the help.