Tony, my mate fitted a used (top half) of a pump for next to nothing, used it for a a few weeks, but now I have just had a new (top half) of the pump fitted and this is so good its like a new machine and the total cost 300 quid, this beats my other 400 psi ninga by miles,
this was a total bargain, any one with a ninga in the north west I know a very cheap service TECK to do all repairs and servicing, drop me a PM for his number.