Yes, and Leica prices follow anything vaguely usable on a Leica; 36mm slip on filters and hoods cost a fortune instead of a pound or two like other sizes. Luckily the Chinese hoods are good and cheap. Luckily I bought all my ex-USSR accessories years ago when prices were reasonable; rectangular lens hoods for pennies and so on...
As for the old USSR made ones, I like the way they started with the Leica II clone but then took it in a different direction and added some refinements to it. It's fascinating to think what might have happened if the cold war hadn't tied their hands and blocked modern technology.