I have purchased a few used mp5 mags for use in my hk94 clone. They all seem to have problems. I managed to get one apart tonight and found that the mag spring was twisted. Kind of like it is unravelling. Anyway, I need to find a rebuild kit for my mags. I have 1 stick mag and 2 bananna type mags, all 20 rounders. Anyone know where to get these???