I've never heard the name "Grielstine", or anything close that I recall. It sounds less Dutch than German, and if it were written by a German, the second syllable would have been spelled, "stein", German for stone. By that time the Dutch communities were becoming more integrated with English and others. This was especially true in Stone House Plains, since it bordered the massive English community that grew out of Newark.
Regardless of nationality, Grielstine certainly wasn't a common name in Stone House Plains or any other community I know of. Where was the marriage recorded, and did you see the original, or a transcription?