G'day, in my family I have a Hinrich Kock/Koch who married Wiebke Rathjen. This Hinrich is described as a cabinet-maker of Kellinghusen (could be your furniture store owner?). I don't have their marriage date, but Wiebke was born 17 July 1812, daughter of Johann Rathjen and Wiebke Ratjen; other children of this marriage include: Anna (b1808 at Homfeld), Hans (b1810 at Homfeld), Catharina (b1816) Johann (b1818), and Henning (b1826 at Homfeld). Maybe your Uncle Rathjen is the Henning who migrated to Australia. Sorry I do not have a reference for where I gained this information. I'll have to look further.