I usually use Wolf or Burnal ammo...both are good and both are cheap...
AK mags, get as many as you can....Steel mags are good, just look for ones in good condition and cheap price...it really doesn't matter where they were manufactured...
My personal preferance for mags is the Bulgarian Waffle mags...they are made of a polymer material and are lighter than the steel mags....they don't rust like the steel mags...they are just as reliable as the steel mags and look a lot better....
www.joken.com is taking pre orders on the Bulgarian mags, they are $11.99 a piece....a year ago they were pretty easy to find, now they are becoming much harder to find...I would advise getting as many mags as you can...
Around this time last year I was paying around $6 for new steel mags and $10 for the Bulgarian Waffle mags...both were easy to find...Joken is the only place that I know has the Waffle mags and the steel mags are now going for around $9 to $10 and aren't as plentiful as they were a year ago....for steel mags you can check CDNN Investments out of Texas...you may also want to pick up a Shotgun News and look for mags in there....
Here's a pic of my VEPR K with a Bulgarian Waffle mag in it....