Assuming the shaft is not damaged having eaten in to the back panel after going through the bearing, you just need a genuine Hotpoint rear bearing. C00142628. I only ever use the genuine ones, even then some last longer than others. If the shaft is badly scored you will need to replce the shaft...
WAB range has a different reset procedure, well at least some of them,try this.
Press and hold start button with the programme off, turn programme one click anti clockwise while still holding the start button,
keep start pressed for 5 seconds.
Unless your condensor is blocked I wouldn't reset a faulty thermostat, it's a single shot thermostat unlike the resettable next to it.
If theres no blockage you would need a heater assembly with a pair of new stats.
Can you confirm the model number. If it is IWC 71252 they have a Sole motor and when the motor brushes have worn the door locks and nowt else happens.
They are held on with a 5.5mm socket size screw. Lean the machine securely back to the wall to remove and check them.
All that muck inside is due to the stainless steel body leaking where it joins the plastic base. There is a tank repair kit with seals and bracing brackets.
Have a close look at the lower spray arm as they split on the side seam and push water out just like that.
Don't think that model number is quite right.