All the G3, HK91, PTR91 and CETME owners in the hizzowse!
CTD is having a sale on used 20rnd mags for $0.99 each.
Feedback reports are coming in that one in twenty mags is a parts-only mag, so buy at least twenty.
And try not to laugh too hard at the prices for M1A and FAL mags.
The aluminum magazines (most likely the ones being sold) are OK when they are new, but they can’t take much of a beating, and must be carefully protected in use. Unless you have the means to do that, don’t buy them.
Sportsman’s Guide used to sell a heavy canvas mag pouch with five magazines for about $25. That pouch was a shoulder-slung model which had individual pockets for each magazine, and it COULD properly protect the aluminum magazines.
If you don’t have some of those pouches, I recommend getting only the steel magazines. They weigh more, but they won’t get crushed as easily as the aluminum ones.
If the source you’re buying the magazines from doesn’t tell you whether they are the older steel or the newer aluminum ones, don’t buy the magazines from that outlet.