If they need a new cell, you can usually find someone to replace it. In the UK, Newton Ellis repair them. I'm sure there is a US repairer too.
I have a Weston III which is very accurate. Its scale has Weston numbers which are 0.8 x ISO. e.g. for ISO 100, set it to 80. for ISO 400, set it to 320, etc.
During his career as a part time wedding photographer, my father went through all of the Weston models. His full time career was a central heating system designer. Sangamo Weston also made timers and controllers for central heating systems and every time a sales representative came to visit, he would give my father a new meter and take the previous one away.
I think he managed to keep them occasionally as I was given a Master IV when I was about ten years old to help me get the settings right on my Agfa Isolette.
Steve.