Scirocco Register

I've bought a replacement Brax master cylinder for my Scirocco Gti 1984 and there's no 10mm bolt on the top of the cylinder as the original ATE one has, does this matter ? I'm wondering if I've got the wrong one! Also there's no blank plug that goes in the side included, and I've chewed the old one up trying to get it out so can't see what it's supposed to look like, anyone know where I can get a correct replacement?
Thanks for any help, hope that makes sense I'm not great at explaining things!