Mark,
The 41 dated holster is not what I would call rare, but they are getting tough to find. The 42 dated holster is far easier to find.
Great start on the Cz-27 collection. Here is a list of some that you are missing
Early Cz-27 (very much like a Cz-24, very early)
Pre War Police,
Pre War Commercial
Pre War Post office
Pre War Rail Road
Pre War Military (1936, 1937, and 1938 examples)
Pre German conversion, nazi marked
DR guns (German Railroad)
AKAH guns
Geco Guns
Early German production high polish guns (you have one of these)
No serial number guns
Early stamped safeties
U guns
Eagle K Police (41, 42, 43, and two different no dates)
Military blue (you have one of these)
Duel tone blue
No serial number on frame (you have one of these)
Phosphate finish War time strawed small parts
Phosphate finish War time phosphated small parts
Phosphate finish War time with stamped take down lever
Phosphate finish War time with stamped safety release
Phosphate finish War time silencer barrel
Phosphate finish Post war No proofs
Post war High polish (you have one of these) (some of these have nicely engraved names on them)
Sanitized (milled off slide top, grip emblem and acceptance mark)
Post war Commercial (45, 46, 47, 48, 49, rumors of a 50 date also)
Post War Military (45 and 46 dated)
Post war Post Office
Post war Rail Road
Post War labor Union
Serial numbers run upwards of 622000. Ok maybe I got a little carried away, but with over 600000 guns you get variation, especially with a large war effort and production both before and after the war. If you have any questions feel free to ask.
Robert