Can I replace the water distribution control on my AEG LAVAMAT 72620 W?

Make: AEG
Model: Lavamat 72620 W
PNC: 91400133100
S/N: 94447070

The teeth on the timing unit that drives the water distribution arm backwards and forwards through the 4 soap dispenser positions are shot on my lavamat 72620W. I've stripped it all down to find the problem and so given the right spares I think I could reassemble it. It looks as though you have to be careful rebuilding the cogs back to the right start position otherwise you will knacker the arm. So given this information, what spares should I order. Worst case it looks as though I need the pan that connects to the water inlet and delivers water to the soap dispenser, together with a new drive unit and full cog assumbly with distribution arm. You will probably realise that I have have made up all these part names so I'd appreciate it if you can supply the correct terms and possibly even a source for the spares. And by the way, yes I did knacker it all myself in the first place. If it ain't broke......... etc
Thanks for any help,
Best regards,
Mart