As far as I understand, many of those brokers are specific to Russia, and get their data specifically from Russian sources which Ukrainians are unlikely to be involved with.

Russian officials / employees are easier to bribe, so there are brokers selling access to car ownership / license plate records, cell phone location records and call logs, passport records etc.

There's a good Bellingcat article on this at https://www.bellingcat.com/resources/2020/12/14/navalny-fsb-...