For what is likely not going to be as good as Plus-X or FP4, I suspect a homemade emulsion would benefit greatly from the larger negative size.
Stable, chemically inert backing paper isn't so easy, however. About the cheapest I ever saw was the stuff on the Shanghai GP3 Chinese film. It seemed almost like children's construction paper. Then you have to print numbers which are chemically inert.
None of this is impossible, but it sure isn't trivial.