By the way, according to table 16 and text on pages above, D-48 was commissioned in 1953, but first 28 guns were produced only in 1954 - we have it available from 1/53 (#582 Russian OOB).
As for unit #802 85mm SD-48 AT - there's no sign, that such variant was produced. On the page
http://vadimvswar.narod.ru/ALL_OUT/T...O/SuPTO035.htm there is only a short information, that a construction of prototype started in 1956 and "the author hasn't found data on SD-48 tests" - and that's all on this gun there (it shows on the first page, that it's a book "Otechestvennaya protivotankovaya artilleria" - "Homeland's AT artillery" by Aleksandr Shirokorad). Russian Wikipedia explicitly says, that SD-48 wasn't commissioned
http://ru.wikipedia.org/wiki/85-%D0%...0%B0_%D0%94-48
It could be replaced eg. with night fighting variant D-48N (small party of 100 guns made in 1957) or more popular D-44N (from around same time).
Speaking of Soviet artillery: weapon #79 ZiS-2 has sabot range 20 (penetration 15), while table 41 here
http://vadimvswar.narod.ru/ALL_OUT/T...O/SuPTO019.htm indicates, that BR-271N (Б*-271Н) still could pierce 125mm at 1500 m.
Regards
Michal