Apparently the printers keep job records for all documents printed, so it should be possible to figure out what exactly he printed.
The cartridges were taken in 07 and 08, the presidential election was 2011.
Very very few printers actually store (over a long period) the content of the documents printed on them, it wouldn't be feasible for one.
They ONLY history they store (and this depends on the printer) are the number of colour/B&W pages that were printed and this is a limited history at best.
Based on the statements by AOS, and the statements from a number of his constituents here and elsewhere, as well as the empirical facts about page coverage, potential number of pages printed per toner, amount of paper required, quality of leaflets that are known to exist, availability of dail printing press, estimated life span of other components within the printers, use of ink/toner by other politicians, reduction in use since the limits came in (the list goes on), you would have to be the most blinkered of supporters to believe that he used all that ink himself on two printers for leaflets for constituents. It just beggars believe that he is still getting support at this point.