Is there a way to prevent my site from being inaccessible in Russia? I think the ISPs there block cloud flare IPs, other than users using VPNs, is there a way to circumvent the block?
So to find anything that works at the moment in Russia, you will need to ask your ISP and/or government for the list(s) of what IP addresses they are blocking, and then compare them somehow.
However, hosting / CDN providers that aren't being blocked by your ISP and/or government today, could very well get blocked by your ISP and/or government tomorrow.