The max levels for all colors is 700, so the OID for Black Toner works for all of them. 

 

I believe the Marker Life count is the amount of printed pages total

 

Object Identified (OID)

Property

.1.3.6.1.2.1.43.11.1.1.9.1.4

Black Cartridge Supply Level

.1.3.6.1.2.1.43.11.1.1.9.1.3

Yellow Cartridge Supply Level

.1.3.6.1.2.1.43.11.1.1.9.1.2

Magenta Cartridge Supply Level

.1.3.6.1.2.1.43.11.1.1.9.1.1

Cyan Cartridge Supply Level

.1.3.6.1.2.1.43.11.1.1.8.1.4

Black Cartridge Max Capacity

.1.3.6.1.2.1.1.6.0

Location

.1.3.6.1.2.1.1.1.0

System Model

.1.3.6.1.2.1.43.10.2.1.4.1.1

Marker Life Count