My step father called a ten dollar bill a "Sawbuck"
A twenty he called a "Double Sawbuck"
A hundred dollar bill a "C note"
& a fifty he called a "half C note"

I never heard these terms except as a youngster from anyone except around my neighborhood (Misson Hill section of Roxbury which is an area within Boston, Mass.) & then only from friends or assocates of my step father.
My question is, does anyone else know on these or similar words used for discribing US paper currency during the 1920's trough to the 50's? I'm thinking it may have been common pre WWII or right in that time somewhere.

Thanks
Barry