Advice on repairs of Skoda Fabia 1.4 TDi

My trusty 6 years old Skada Fabia need some minor repairs:

1) The driver's door lock pin is sticking, but the central locking mechansim works fine for all the other door including the tailgate lock.

2) The tail gatewiper washer is block where can I find instruction to rectify to unblock it.

3) The tailgate wiper cap need replacing, where in the UK will it be most easy to get a replacement.

I live in Madienhead, Berkshire.

All advice welcomed.

Terry