225 Slant six Rocker Arm Adjustment Screws?

Does anyone know where to get these? RockAuto has been out of them for (apparently) years, Summit Racing isn't getting any until June 13th, and I'd like to have them in under a month, in time for my rebuild of the engine. It's 3/8 x 24 threads with a 5/16ths ball on the end, and apparently the most valuable commodity in the world.