If you need new armrest bases, they are cheap! Chevy people have reproduced and sell at many sites. Here is one for $35/pr http://www.lategreatchevy.com/full-size-chevy-armrest-bases-chrome-hardtop-or-convertible-impala-1962-1964.html#close
As for the top pads, I just recover them with the correct silver vinyl. It takes some spray glue and fitting, but they come out great. I have some silver vinyl if you want to try.