The main site for Friesland genealogy research is: https://allefriezen.nl/
However records from 1650 and further back often don't survive, but it is still worth having a look. A quick search for "Haring" and variants in the period 1500-1650 brings up 4,800 records.
When using AlleFriezen, I would keep in mind that in Friesland many surnames have a very wide range of spelling variations, and that some surnames are very common, so do be careful when assuming that two people with the same name are actually the same person. To have any chance of success with Frisian records, I think you will need to have a specific place of origin, occupations or parents names from the records in Germany. Perhaps you could look up the history of post-Thirty Years War migration for more clues.
Out of curiosity, what sort of DNA testing are you doing? Is it Y-DNA?