Mike,
If you really would like to fix the wind vane and anemometer, I would recommend contacting APRS directly and having them factory serviced. These are in the same class as Maximum and Downeaster wind sensors, essentially same specs and mechanics, same design. These sensors are not made to be serviced internally by the end user. If you go to their anemometer page, The bearings are custom made Teflon, so even if you can service it yourself, you will have to order the bearings from them. The anemometer also requires calibration. If there’s a lot of play, your bearings definitely need replacing. But they would anyway, all wind sensors should have their bearings changed out every 5-10 years or so, depending on the use. Yours would be far past when they should have been changed out.
As for high end, these APRS sensors are really in the prosumer class, high end would be A.S. Richards, Dyacon, Vaisala, Columbia, Climatronics, Met One Instruments, Kriwan, etc. A lot of prosumer level sensors are used for monitoring, unless it is highly critical precise monitoring that is needed. Texas Weather Instruments was the most common one used by a lot of companies when they were still in business.