ALL 21H and F (with dovetails) = 19mm
ALL ZG-47 = 19 mm
ALL 600, 601 and 602 = 19 mm
ALL 550 = 19 mm
465, 527, Fox, Fox II = 16 mm
the .22 = 11mm
It is a very elegant and timeless system that I love. I have one piece mounts from the late 40's that mount to my present day 550 and vice versa.
Conetrol makes very solid mounts that are fussy to mount to the scope and to get the scope upright (the seamless rings need to be man handled into positin and the scope tends to twist) - but when set, are very solid. I tend to prefer the ones that have 4 screws per ring. Some do not like the 4 screws as they find it difficult to get even pressure across the four screws.
I prefer the BRNO/CZ rings as they are built for the system.
Leupold are fine as well.
Lynx has both two piece rings and a one piece base with "turrets" that allows you to change ring diameters easily from 26 mm to 24.5mm to 30 mm (the one piece Lynx have windage adjustment that may get you out of a jam but may be hard to source. Of course they are made in Austrlia but they will not ship (to me anyways))
The BRNO/CZ rings are overbuilt (as always) but when set - well, mine do not move.
As for height -- yes you may end up with a slightly higher "cheek or jaw weld" than you are used to but in the end for many of my rifles I end to prefer the higher head stance for effective hunting purposes. Of course the sniping, close, low weld is desirable for long range precision shooting but i find you get used to it.