Any one know where I could find one? I have a post ban Norinco mak 90 with stamped receiver that looks to have been made for an under folder. sportster I believe they called it. bought it in 92 or 93 on an E2 salary, had thumbhole stock and wood fore grip. bayoneted lug is ground off, threads removed from barrel, tang welded to slant cut... Clinton style. would love to have a under fold stock on it.