I ran this on my Evo until I found my Hera SFU. Free to a good home. What can I say about it? It's big, it's bulky, it's free, and lastly it works.
http://www.primaryarms.com/utg-ak-47-side-folding-stock-adapter-tl-k7fad01
http://www.primaryarms.com/utg-ak-47-side-folding-stock-adapter-tl-k7fad01