I've just tried another fix on it, I've removed all seals and replaced. All the factory grease applied to the internal of the pump has been removed leaving a slight film of grease that remains after a wipe down. I fit a grommet and the leak from the pump as seen above has finally stopped.

I now have a massive leak at the lance end, where there's no possibility of fitting a seal. PTFE tape has sorted the problem out.

It now currently works as it should, I'm happy now, but really shouldn't have had to spend all this time sorting it out. Still thats what you get for buying of eBay trying to save a few pounds not buying of the high street.