Okay, I have found some old material that you may find interesting. I looked in W. H. B. Smith's "The Book of Pistols and Revolvers" (Orig pub 1946, Supplemental Material by Kent Bellah 1960). On page 340, it gives the usual data for the time regarding the 9mm Luger: 115gr, 1150fps, penetration of 7/8" soft pine boards - 10, barrel length - 4" (plus dimensions, etc.). This information was from the Western Cartidge Co. Actual velocity from real world guns would probably not have been much lower, because of functioning. I looked in two other books of the same period and found the same data, but in the fine print found that it was all supplied by the same company!
Now it gets a little more interesting. On page 339, a table has been added (don't know in which edition it first appeared), showing some data by the H. P. White Company on tests of various 9mm loads. Four of them are relevant to our discussion of 9mm load levels. They list name, weight, velocity measured 20' from the muzzle, and penetration of yellow pine in 2" planks at 25' (I assume with no spacing, unlike the usual 7/8" boards quoted above). The pistol was a Walther P-38 with a 4 7/8" barrel.
(a) Remington Commercial 124gr 1193fps 5"
(b) Western War Contract 115gr 1231fps 4 15/16"
(c) German Govt. 1918 123gr 1207fps 5 19/64"
(d) German Govt. 1941 (Pist) 124gr 1242fps 6 3/4"
The other loads were submachine gun ammo, and the one Glisenti load (weak version of the Parabellum). Load (d) had the greatest penetration of any of the loads tested, and I wonder what the construction of the bullet was (the German subgun ammo had weights of between 91 (tracer) to 99 grains, perhaps this could be the sintered iron projectiles I've heard of). I would guess that the Western War Contract was probably for an Allied nation, seeing that it's a lot faster than Western's own specs listed earlier. The Remington Commercial seems to be pretty much identical with current M882 ammo, and seems hotter than the usual commercial loads of the day. In the 1960 edition Supplement, Mr. Bellah states that Winchester loaded special ammo in the 50's for Army tests, that fired a 115gr bullet at over 100fps higher than the U.S. commercial loads. As you probably know, the Army tested Colt Commander and S&W 9mm automatics, for possible adoption in the 50's. The project was discontinued in 1956, since we had a bunch of 1911A-1's (which probably surprised no one).
I just thought that all this shows that the usual world standard for 9mm Parabellum ammunition is about the same as 9mm NATO, and that SHOULD mean that any decent 9mm pistol is suited for that ammunition. Discussion, anyone?