Be very careful, if you modify that to accept double stack mags, you MUST replace parts with US made parts. Section 922r is still the law. You cannot have more than 10 imported parts. The single stack is excepted as it only holds 10 rounds. You change it out to high cap, the rules kick in
On an AK there are 16 effected parts. Make it a double stack and you must replace 6 parts with US made parts. A US made magazine counts as 3 parts.
While (I understand) no individual has yet been prosecuted for violation of 922r, we as a forum have an obligation to keep you informed as to the law (as we know it) and there may come a time when ATF DOES go after individuals for such violations