Russian city satisfactorily importing manuscript (4)
I believe the answer is:
omsk
'russian city' is the definition.
(city in Russia)
'satisfactorily importing manuscript' is the wordplay.
'satisfactorily' becomes 'O.K.' (synonyms).
'importing' means one lot of letters goes inside another.
'manuscript' becomes 'ms' (abbreviation for manuscript).
'ok' going around 'ms' is 'OMSK'.
(Other definitions for omsk that I've seen before include "Russian city" , "City of Asian Russia" , "Russian port" , "City in Siberia" , "City of south central Russia" .)