Ha ha! Great line.
Now, I can't especially say which film it's from as Sir Sancho gets so many good lines in so many films but summat keeps me hankering for him maybe saying this as Gordo Watch in Arizona Colt. He does get some particularly great lines in this...
"My father had a musical gold watch. He told me "Gordo, you'll have this watch when I am dead." So, five seconds later, it was mine!"
Could well be wrong, but worth a look?