While cleaning and painting the shift lever / shift bar I noticed that years ago I had tweaked the design to reduce play in the shift lever. There was excess movement in the lever to bar junction. Your situation may be different.
Two thin washers can be added on each side of the shift lever tang (inside the fork of the bar) to take up the play when the shoulder bolt is torqued. I ended up using .030” washers. Thin washers are available in various thicknesses from several online sources. Grease all the contact surfaces.
Test to be sure that the lever moves freely when the shoulder bolt is torqed. The stack of washers and shift lever tang should be set slightly less than the thickness of the tang plus the one side of the bar fork.
There have been a lot of suggestions over the years; I'd add in that polishing the end of the shift lever (it looks, stock to have just been cut down and ground out...finely polishing the tang and fork inside surfaces can't hurt and may well lessen the wear.)
Also, I've gone to using sintered bronze bushings (see photo) and liberally coating them and the bolt with moly grease before assembling. Have made this change in every Europa, and, while the original design is marginally acceptable, these seem to last longer (when I sold 693R, the shift feel was just as nice as when I first returned her to the street) than the nylon replacements most suppliers are providing.
If I had the equipment and time, I'd probably machine a larger fork and lower bearing arrangement as here:
https://www.gglotus.org/ggtech/europa-shifter/europashifter.htm , but, don't have a machine shop to work with, so, pretty much sticking with what I've got.
