Parameters of a brake drum?
 

Hello.
I ask to help me with a choice of a drum for a Cadillac Fleetwood Brougham 1991 RWD in Moscow. The old drum hasGM 1244835. To it corresponds AcDelco 177-360 (11х2). But such drum is not present at us on sale and not present on rockauto.com. Onrockauto there are various drums 11х2. The some people have additional parameters:
3-3/8" Drum Width.
4-1/4" Drum Width.
What do these parameters mean?
Professional Grade Outside Diameter 12.8"
Professional Grade Outside Diameter 14"
PG Plus Outside Diameter 13.37"
What else of stereotyped drums (for example with rockauto) I can buy?
Also on an old drum there are following inscriptions:
Max Dia 11.09
C289
08671001
Thanks.

RE: Parameters of a brake drum?
 

11x2 is a pretty standard drum, you could go to www.usapartssupply.com as they have a lot of Cadillac brake parts. Good luck.