Hi Mitch,
Not Dutch but British date letter script D for I believe 1978, Import mark for Chester see;
http://www.925-1000.com/importmarks.html
However the SBL mark in a rectangle is not a Dutch maker's mark, funny enough it look exactly like the British importer’s mark of Samuel Boyce Landeck, London 1879 used, known importer of Hanau style silver with pseudo marks. The scene is typical Dutch, so to speak.
For Samuel's mark see:
Known British Importers of Hanau silver:
http://www.925-1000.com/Fgerman_hanau_marks_01.html
Please check for proper Dutch hallmarks, under the two putti’s I believe I can see a circular mark which could be a little Dutch Minerva head (assay office mark), the marks could be very small and spread over the object. You ought to find a lion rampant, date letter and Dutch maker’s mark.
Oel.