Adding a stock to a firearm formerly classified as a pistol would require the tax stamp. Even if the rifle had a 16.5 in barrel.....which you won't find on a Draco.... you've created a rifle from a pistol, making the tax stamp a requirement regardless, at least as I understand it. If you are going to have a 16.5 in barrel, you're better off just buying a rifle version of the AK that already comes with a 16 in barrel, eliminating any NFA problems. Theres no real point into pinning on a flash hider that brings the barrel length of a Draco equal to that of a standard AK, unless theres something I'm just not understanding about your post. Making a Draco into a rifle...but with a barrel length of 16 in plus....just seems to be an exercise in futility and wasted money. A draco SBR makes sense....a Draco rifle with a barrel as long as a standard AK, and a redundant $200 tax stamp........well, not so much