suspension parts wanted

Unknown

I've got a 1978 Concord with the 258 inline 6 and the torqueflight 998 trans, and what i suspect to be a dana 20 rear end. the leaf springs/spring shackles are quickly eroding to dust, to the point where i'm no longer driving it for fear of collapse.

i am wondering if there are parts kits available or interchangeable for this particular axle, maybe from a CJ5 or a chrysler of that era.

any suggestions?