[atlas] list of country codes / UDM via API limit

Hi all, is there a list of country codes that have active probes in them? I've used the ISO3166 list but am finding that many CCs do not have probes in them, so setting up those UDMs is moot. I am also running into what appears to be the limitation of the amount of UDMs that I'm allowed to setup using the API: around 25. Has anyone else run into that limit? Is there a way to raise that limit somehow? Thanks, ~paul