Exile machine has Arsenal 10 rounders (Bulgarian Polymer) in stock for $20-some odd bucks. The profile is more similar to the steel, so it should work well.
I have a Tapco 10 rounder laying around (donated to the junk pile), and it's thicker/longer, and the feed lips seem a little odd. I should test it out and see what happens too.
Scrounging up some steel 10 roudners might take some work- my steel mag was bought at a gun show probably about a decade ago! Chinese made, works great in other AKs so far (usually used as a 'tester' mag).