just some casual thoughts;
I take it what you are saying is there are TWO DIFFERENCE ORIFICE SIZES the kit, and not that there are two more obvious lengths / etc. that might be diff.
Can you eye ball the difference in between the two diameters ? I think yo uamy be surprised how well a small dia diff could be eyeballed side by side
If not, perhaps you could rig them up as a drain of a fix water volume, and at least get an idea of the relative sizes from the time to empty.
Then ( or if you CAN visualize the diff ) see if you can find one in a salvage yard to compare.
I have some fresh rebuilts of unknown source but I dont have a any pins to check NOR would I recommend some one risk chipping up theirs.