https://board.moparts.org/ubbthreads/show...=29#Post8242219

I made my own springs for my '70. Bucket seat springs may use the S bend spring wire found in most furniture and that can be bought from Upholstery Supply stores. C.S. Osbourne sells bending and forming tools for the S bend wire. Post up a pic of the broken springs. you may be able to repair the broken springs rather than replace them.
http://www.csosborneupholsterytools.com/category/Spring%20Clips%20_%20Tools

http://www.diyupholsterysupply.com/upholstery-spring.html