Thanks David,
I don't have the pen apart yet to check the remains so I'm guessing as to the material.
I guess I'll have fun knocking out the blind pin from the plunger cap to start with.
If I can't find the parts I might experiment with making my own seals from gasket material, syringe plungers and anything else I can find. I do know about the left and right hand threads etc...Lucky I found that out.
I have found a site in the UK that I shall e-mail tonight (my time), I hope they still have some.
Gary