Hi Mick
Thanks for the reply,I think a previous owner has been at the pistol before as the 'plate' (1300-008) is missing ,which I only noticed after looking at the pars list.
I'll give it a whirl putting it back together with an o ring there instead of the flat seal - the Pringles in the pic I sent is the remains of the flat washer which seems to have been cut off most likely due to the bevel on the part 130-057.
Will let you know how I get on
Regards
James