Yep, also important to remember that in some countries (I don’t know if Russia is one), VFR private avation is a pretty rare unicorn. So there might not be conventional charts.
I know in some parts of the world the charts are still controlled by agencies that will not make them freely available. They are a revenue source. So getting them for hobby purposes isn’t reasonable.
You are correct if you apply the U.S. style rules to that marking it would indicate restricted airspace. Even in the U.S., ‘Restricted’ is sometimes actually ‘Prohibited’. A great example of this being the area around Groom Lake Nevada, more popularly “Area 51”. This airspace is R 4808 N, a restricted airspace.
But I can guarantee you that airspace operates as if it is 'Prohibited" and you will never get permission to overfly that area. I suspect the reason it was done this way was when that base was actually still secret, they didn’t want to show a Prohibited space out there that would attract attention.
Typically a ‘restricted’ space is available to fly over sometimes. Normally the restriction is military, but if nothing is going on in the area, the area may be deactivated… And you can get permission to enter. But, places like Groom Lake, that never happens. It is prohibited even tho not marked that way. Kind of next down the list in that regard would be Military Operations Areas (MOA), these are often available to fly through, but will be activated when military activity is going on, and during those times will require special procedures, or may not allow you to enter. Those are all over the place in the U.S. Notes are on the charts as far as what agency to contact for information.
Anyhow, sorry with your difficulty finding decent world vfr coverage. You’re not alone!