I don't see the prices going down too much after the ban.
IMI is not making these things any more. They can legally import as many as they want to if they were made prior to '94, which is why FAL, AK, and G3 magazines are dirt cheap right now, and why Galil 5.56 magazines are available and relatively inexpensive ($20-$30).
I've picked a few up while searching the EE forum, but the best deals I've found were some IMI converted M14 magazines for about $70.00.
Go ahead and buy the ones from CDNN. I can't see them getting any cheaper.
The only way they'd get cheaper is if someone in the USA decided to start producing Galil .308 magazines, and....
#1-the market isn't really there for someone to tool up to do so
#2-the quality of the US made magazines would be HIGHLY suspect.
These magazines have always been expensive. I remember paying $50.00 for them in 1990.