My expectation is that mag prices will fall fairly slowly, reaching '94 levels in a few months or so. At first, the extra demand for new highstandard capacity mags and the rush to produce and ship more may keep the prices high, depending on how well it was all planned, but everything should normalize fairly soon.
I wouldn't expect to see much change in the price of new rifles. They may drop somewhat over the next couple of years as customers don't feel that "get it before it's banned" urgency, and suppliers become more willing to invest in producing those rifles when it becomes clear they won't be banned again at any moment.
Former pre=ban rifle prices have probably already been falling to new rifle levels. I expect they'll stay there or lower, unless there's some reason for them to be collector's items. Of course, some asshats will probably continue trying to get ban prices for their stuff, but that sort of thing's nothing new.