They are new and will be fine in your 72
According to napa's website yes that is the correct # for a 72 Scamp.
Pretty sure the lower control arm bushings were the same for quite a few years.
http://www.napaonline.com/Search/Results.aspx?Ntt=267-3193&Ntk=Keyword&N=599001+101972+50056+2056023
Have you checked on the condition of your bushings/suspension components?There's probably a reason these were purchased.