this is the third week in a row that this question has been asked/a new thread made.
Fantasy football rule #14:
NOT EVERY STUD HAS A TRUE HANDCUFF. In these cases, you're "handcuff" is whoever the next best Rb on your roster is.
FWIW, should Westbrook go down, a true RBBC would occur in Philly, with Buckhalter getting the majority of normal carries, Booker seeing most third down and obvious passing down work, and Hunt seeing goal line/short yardage work.
Booker has a style similar to Westbrook, and is capable of runnng many of the recieving plays Westy does, but he's not anywhere close to as talented, especially as a runner.
Should you lose Westy, Booker might suffice as a flex in PPR, Buckhalter as a flex in non-ppr. If you consider a flex RB a "cuff" for your stud RB1...then you aren't ready to win a championship anyway.