Warbird Information Exchange

I'm starting the search for various items for the flexible gun for my Fairchild AT-21 project. A couple of the items, I've located, but there are a few that I need to find a source of information and specifications on, to aid my search. I would think that most are common to the standard M2-.30 cal, but would sure like to know before I start getting too far in the search. If anyone can point me to sources for the specifications, I'd be most appreciative. Here's the list of what I'm looking for, as called out in the aircraft books:
A-5 Link Ejection Container
A-5 Case Ejection Container
L-4 Ammo Box
A-1 Ammo Box Holder
A-3 Ammo box Mount
C-18 Gun Mount Adapter
A-9 Post Sight
L-2 Ring sight

Sources for the items themselves would be good too. I've got this posted over at the "G" also.....
Thanks for the additional help.

BMG Parts should have much of what you want. https://www.bmgparts.com/anm2.html

Yep, unfortunately, I'd be very deep in the 4 digit costs from them. Just the ammo cans would be a couple of thousand bucks...