I know it!
East Germany made steel ones, I think Bulgaria made plastic ones.
Bulgarian circle 10 mags....very expensive if you can find them.
Here’s a conversion for stanag ar mags in your .223 ak
https://www.youtube.com/watch?v=PAjidZr5D7o&list=UUZ-qxagOkAmCEP-Tu6YliUQ&index=1