Perry,
The load data in COTW shows using cast bullets from Lyman Molds #32359 and #32360. The first of these is a 115 gr bullet and the other is 150 gr. Since the "32359 bullet was sometimes used for 8mm Nambu, I would guess other bullets intended for the Nambu would work. Also the bullet for the .310 Martini Cadet should work, after a fashion, they are intended to be outside lubricated but are the right diameter for loading with the grease groove inside the case. If he has cases, he should treat them with care, they will be hard to replace. The case has about the same head diameter as 32-20, 25-20, and 218 Bee; but is about 1.77" long, whereas the others are 1.32-1.35" long. If I had the rifle, I think I would just use 32-20 cases and the #32359 bullet( I have the mold and cases "on hand" already).
Mike