On points.
Whether employees of NKVD could shoot Poles from german’s pistols of calibre of 7,65 mm.?
The answer - no, could not.
Pistols of calibre of 7,65 mm. were very big rarity in the USSR. Some thousand trunks of such calibre remained since times of revolution (from private weapon shops) and civil war (from interventionists).
These pistols were used as award weapon, and also given out as a hand arm to pilots and diplomatic couriers. In NKVD it use employees of a foreign department for performance of tasks on physical elimination of especially dangerous emigrants used them only.
There were some more thousand pistols of the Soviet manufacture of a design of Korovin of 1924. The design was the extremely unsuccessful - 56 details and very hard descent - and to the middle of 30th years these pistols have completely left the use because of breakages.
Accordingly for a small amount of pistols it was not required also an ammunition. All needs of the USSR for patrons of calibre 7,65 completely were provided with manufacture of such cartridges on Podolsk mechanical factory which began in 1925-26.
Any documents on purchases of the USSR in Germany in 20-30th years of pistols “Walter” in archives of the German Ministry for Foreign Affairs it is not found.
In Germany In 20th years of the USSR really bought in Germany pistols. But absolutely other pistols - “Mauser” of calibre of 7,63 mm. Documents on these transactions are. Except for that USSR has bought in Germany the license for manufacture of pistols “Mauser”.
Whether could buy the USSR in Germany cords?
No, could not - in 20 - 30th years of the USSR itself actively sold hempen cords across all Europe.
As have defined, that steel sleeves have been made in 1941?
Have very simply defined - till 1941 steel sleeves were not made at all. Anywhere in the world. Germany started their release owing to sharp deficiency of nonferrous metals. In the USSR manufacture of cartridges(patrons) of calibre 7,62 with steel sleeves began only in 1943.