Good topic and although I don’t work at a school, I have noticed the following.
1) Most Universities hold alumni events overseas so they would be the best source. Uni’s also have specific chapters for each country. (or state)
2) I’ve found mainly private boys schools and some top co-ed private schools hold events overseas.
3) Most popular places I’ve seen are London, Singapore and now China. (Hong Kong also)
4) Schools that have a sister school in the country tend to host more events.
May I suggest reaching out to individual alumni directors from these schools via LinkedIn! I’ve found this to be the best way to engage with people directly and about a specific topic. DO you plan to host a panel?
I can think of a dozen schools just writing this so you shouldn’t have an issue.