I checked with Simplify (the MC Stripe clone), and they're cool with firearms and accessories sold online, and firearms sold in-person with card swiped. They're going to get back to me on whether an FFL could sell online MOTO -- I'm pushing them to allow it IFF the FFL ships to another FFL, which is federal law anyway.)
http://www.slate.com/blogs/browbeat/2012/08/17/ebay_bans_mag...