My friend and I recently bought a few from Marstar.
They are made by Norinco and hold 7 rounds.
The blued ones were, like, $9.95 each and the stainless were a couple of bucks more (13 or 15 - can't remember exactly).
It was taking a little long to fill my order so they actually gave me the stainless ones for the price of blued - a nice gesture on their part, methinks.
These are great "economy" mags - work great - and the stainless look real nice too (nicer than I expected).
Again, they are not as nice as, say $40 Metalform or Wilson Combat units, but they are great for the price (economy is the word)...but they WORK.
Plus you're buying from a CGN sponsor who is selling right here in Canada.
Good luck on your mag quest!