Filmed willing American entering borders of Canada (2,6)
I believe the answer is:
on camera
'filmed' is the definition.
(I've seen this before)
'willing american entering borders of canada' is the wordplay.
'willing' becomes 'on' (I've seen this in other clues).
'american' becomes 'amer' (rare abbreviation).
'entering' indicates putting letters inside.
'borders of' says to hollow out the word (remove centre letters).
'canada' with its middle taken out is 'ca'.
'amer' put inside 'ca' is 'camera'.
'on'+'camera'='ON CAMERA'
(Other definitions for on camera that I've seen before include "Being shot" , "In process of being filmed" .)