my 1982 Bmw 520i (6cylinder injection) sports an electric speedometer. At the moment, the needle shows the correct road speed while driving but the trip recorder stopped counting the kilometres. I removed the whole dashbord instrument unit and separated the speedometer and noticed a spindle with a split toothed plastic gear wheel (about 5mm diameter). Is it worthwhile to replace this damaged gearwheel? or maybe try to obtain a similar complete speedometer?
Pls note that i am a DIY type. Any help will be appreciated.

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