i filed the grooves down on mine and stuck a JSR adaptor on it . Loctited on . I never tried to see if the front sight would go back on as i use and removed the open sights .
i know some people have used a needle file and cut grooves in the adaptors to save filing the barrel grooves. .
Ian Blade newman on facebook used to do shrouds but i'm sure he was reported for making them .i think he does a parts kit now to do it legally but i may be wrong .
Tinbum used to do shrouds too . Not sure if he still does .
i'm not sure if the VCR act comes into it if people make them and send them via the post like a shop can't send a new moderator through the post . only if its a warranty replacement i think but i'm not sure .