If I understand correctly, this suggestion is to combine opium (or other opiate) with a job of some kind. Probably any addictive drug (such as alcohol?) would work.

The trick isn't combining the two - it's making the two inseparable. I would expect that otherwise, people's brains correctly solve the "credit assignment problem" and figure out which aspects of the combined experience are causing the pleasant feelings, and which are extraneous.

Possibly this is the analogue, in human-motivational-augmentation, of the wirehead problem in FAI.