I'm still here for now, only planning on leaving around May this year.
Initially I modified the 750 rotor, but found most of the 750 pumps I bought were badly pitted and could not be used, so now I make my own rotors to my spec. these I have wire cut from a special steel and then liquid nitrided.
Just done a pump for a customer it was my last rotor, but I will try to do another small batch before I leave.
Kevin