There be no payment needed mate and you're not taking the piss, I'm sure you'd help me out if I needed a part and you had one kicking about, I have a new piston seal if you want it as well (and a breech seal if you need that also), I just remembered that the inside diameter of the spring is 14mm, if that helps (just in case you have any springs kicking about).

I'll have a look in the man cave tomoz and let you know what I find.

Pete