Where could I start to look to find any further links to the family in Poland?
Try this Polish genealogy website - I have already included the search for Rawisinski surname:
geneteka.genealodzy.pl/index.php?rid=A&from_date=&to_date=&search_lastname=rawisinski&search_lastname2=&rpp1=0&bdm=A&w=05ld&op=gt&lang=eng
The Rawisinski sounds Polish. Although it's rather very rare name now. The more "Polish" spelling would be Feliks Rawisiński. The feminine form of this name is Rawisińska.
Little more info about Rawisinski (probably himself) here:
listakrzystka.pl/?p=240260