As stated,
E-bay used the fact that the VT shooter MAY HAVE purchased a magazine via E-bay as their reason for banning many components. Not all, just many.
You can still buy reloading presses and dies (gee, the brass and bullets can't be turned into cartridges without those), scales (for weighing out the proper powder charge), manuals (gotta have recipes to make those cartridges), ammo boxes (for storage of the cartridges), lead for cast bullets (self-explanatory), bullet molds for the cast bullets (self-explanatory) and other various components. Just not the brass.
So there is a little background on the E-bay ban (or partial ban).
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That said, you can check the Reloading Components and Gear section of the trading post here at THR. There are various opportunities to purchase brass being posted all the time.