Agitator for 950 eziset Simpson?

I have this machine which I purchased from Retravision with a 5 year warranty it is 4 years old.
White washing white bedlinen I heard a loud bang in the machine while it was washing. At the end of the cycle I noted there were fragments of plastic in amongst the sheets and a large hole in the bottom of the agitator. ALL my beautiful French sheets had little rips in them and can no longer be used..I assume this was caused by the hole.
I have tried to remove the agitator but cannot budge it.
Before I try to purchase a new agitator I want to be sure that this is not a common problem. This machine is only ever used for white bedlinen because of its lint problem.