www.elitefourum.com/t/some-early-japanese-pokemon-trophy-card-research/11698/1
www.elitefourum.com/t/early-pokemon-tournament-participation-cards/10612/1
The threads I mentioned before - Both you and @mkpokecc commented on them.
Quoted from @smpratte on the second thread as it seems to be the most helpful comment towards this topic, however this information may have since changed if more information has emerged - “The Kamex White R - I do not know the exact amount of copies of this card but I always placed it with the 9th lucky stadium. However, I have personally seem more copies of the Kamex than the 9th. I would say I have seen double the amount including both private and public sales. This is not definitive proof there are more of Kamex, but in my experience, it leads me to believe there might of been another possible distribution.”
Edit: I think the distribution number being between 100-200 seems quite possible, but I feel any more than 200 would be a stretch still.