[oletrucks] Brake Drum question

["Parkinson, Rob" <Rob_Parkinson@jdedwards.com>]

Hi - My son's 51 3100 supposedly has  a 73 Suburban rear end in it.
I'm trying to replace the rear drums, but am having trouble identifying a part 
number.
They appear to have been 11 inch by 2 3/4 inch.  They have a casting number of 
GM 333047 on them. Does that ring a bell for anyone?
Anybody have a clue where I can get a x-ref number so I can order them through 
a NAPA or someplace local?
I've already tried NAPA, but without a part number they can't help.  I've also 
tried a GM dealer - no luck
Thanks in advance for any help.
Rob
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