Wow impressive list, thanks.
There is ammo available; you just have to hunt around for it and be prepared to wait from 3-8 weeks for delivery. I’m still waiting for add’l .50cal mags (proprietary) from Alexander Arms for my Beowulf; order placed Dec 23rd. Getting 1,000-rnds of 335gr HPs (proprietary) from them took 6mos, in late 2011.
Ordering from that list was easy, cheap & quick until 11/6/12 - and I stockpiled a LOT of ammo & mags for years - and the 12/14/12 CT massacre brought it to a screeching halt.
Hope it helps you.