See if there are any MIB objects in the CISCO-ENHANCED-MEMPOOL-MIB that could fit the bill.
I just did an snmpwalk and got this:
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.1 = STRING: Small
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.2 = STRING: Middle
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.3 = STRING: Big
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.4 = STRING: VeryBig
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.5 = STRING: Large
CISCO-ENHANCED-MEMPOOL-MIB::cempMemBufferName.9.6 = STRING: Huge