I'm sure you could solder together some 1kV 1MΩ resistors, but if you can buy a 10kV probe designed, built, and tested by people who do that every day, betting

I'm sure you could solder together some 1kV 1MΩ resistors, but if you can buy a 10kV probe designed, built, and tested by people who do that every day, betting your life on your DIY creepage allowances may seem unappealing.