Rubber bushings on the levers and sieves are important, keep them up in shape, loose ones cause failure_breakage of parts connected, pkgs of complete sets are available a little cheaper, B94553 pkg 20 for 16 series except last ones built with long sieves are $79, you can buy just one but most likely combine of this age will need a set of them complete, cheap insurance, be warned they are not the most fun to install correctly.