swapability of sway bars?

looking to get a front sway bar for my 73 duster. i'm looking on the ebay for used (cheaper) units. do older bars fit in? the addco site shows the same part number for virtually all mopars. just different end links.

http://02bbfb5.netsolhost.com/Plymouth-Susuki_AntiSwaybars.htm#Plymouth

did they change the suspension that radically for '73s?