Tidied up my Old Webley Vulcan MK2 a few years back after it spend many moons in the loft, after sticking a new sear spring, breach washer and spring, plus stripping it and cleaning all the old gunk out of it its now shooting sweet as a nut.
Don't worry about replacing the piston washer on these guns as they seldom wear, they somtimes crack due to dry firing but the fact they are PTFE means they stay slippery without much wear.
this is my old baby about 12 months ago shortly after moving here.....