In the data on B&W aerial film, Kodak mentions "dyed-gel backing". I don't know if this is the same as antihalation backing. There is also the phrase "extended red sensitivity ", which may or may not mean something in term of general photography. I recall someone on one of the large format forums using aerial film cut to sheet film sizes and being satisfied with th results. I'll have to search and see if I can find that post.
If I were looking for B&W film right now, I would search for any commercial studio that does aerial photography, and see if they have any outdated film they might sell at a discount. If that turns out to be a dead end, then buying a new roll from Kodak would seem to be the alternative. Actually, the new price of approx. $4/foot isn't all that horrible. I think the last 8" Verichrome Pan I bought before it was discontinued was close to $25 for a 6 foot roll. Of course that was spooled to go directly into a Cirkut. I've seen posts recently that film costs are going up a lot due to the increased price of silver. I wonder if 9 1/2" aerial is still being sold at the "old" price? The B&H price of around $900 for 250 feet may seem cheap a couple of years from now.
I seem to recall Bill McBride showed me pictures of a Chinese pan camera that used 8" to 10" width film. I've always wondered if there is a China source for film used in that camera.