Cheaper than Dirt and CDNN often have them for $22 as well. That's what I paid for an order of G22 mags last month from CDNN.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
US Army 1966-69, VFW Life Member, Retired Geek