I can provide you with 16-mm. Gigabitfilm 40, perforated along one edge 0.3000". Its from 2005. You can have 100, 200, 400, and 800 feet. Exposure index ISO 40 in daylight when processed in the original Gigabitfilm chemistry. The stock has half the thickness of common films, so 200 feet can be wound onto a 100-ft. spool. $29 for 100', net. Gigabitfilm is panchromatic.
Else you might find a solution with Ilford. They discontinued Pan F, FP 4, and HP 5 as ciné stocks. Who knows whether theyd find the way back to converting to 16 if one placed an order large enough?
Fomapan R must be reversed or the negative is covered by the black silver anti-halo subbing its got.
Why not buy directly from
FilmoTec in Germany? They make more than only UN 54 and N74.