According to the Devon Family History Society online indexes, they have records of the following marriages:

Surname 1754-1837
BOSANKEE...........1
BOSANKOE...........6
BESANKO.............1
BOSANCO.............1
BESANKA..............1
BOSANKO.............5
BESENKER............1

I already have details of the following marriages in Devon:
John BOSANCO 1748, Holsworthy
Elizabeth BOSANKOE 1772, Holsworthy
Elizabeth BOSANKO 1777, East Stonehouse
Mary BOSANKOE 1780, Holsworthy
John BOSANKOE 1785, Holsworthy
John BOSANKO 1791, Stoke Damerel
Richard BESANKO 1809, Exeter
Sarah BESENKER 1814, Stoke Damerel
Thomas BOSANKOE 1817, Hatherleigh

Can anyone help with the missing seven marriages?