Drayton diverter valve queries (Worcester Bosch Greenstar Heatslave 18/25 combi)

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I have an external oil boiler Worcester Bosch Greenstar Heatslave 18/25 combi installed 2010. It has a leaking diverter valve stem, it has a 3 ports with a 2 way A B motor head. Can I replace it with another valve like this being a 2010 boiler I think it should be the type with fiber washers rather than the rubber o'rings ?

The other issue is the motor head which has 'Diverter Valve' written on it and number 8-718-684-238 had broken (it has 5 wires). The micro switch had a small tab snapped off and the center hole 'boss' hole has a crack in it. I put a cable tie around the boss and packed out (cardboard) behind the switch so it now works. Is it a standard 5 wire ZA5 / ZA6 ?

All in all it's a lot cheaper to buy two parts rather than a complete diverter valve assembly vale and motor.

Thank you.

PS I can add picture if needed !
 
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