towards the end there are drawings / dimensions of all the pads
try to see if you find one with race compound big enough to machine out of it your round diameter
even if the round shape is a bit truncated by some mm, it could still work.
thats what i do to put modern compounds in my old brembos
Back at the time i checked with vintagebrakes.com and he had nothing for the stock honda flag calipers other than Ferodo platinum compound. Works ok-ish for a few laps, then its downhill...