Very cheap, quick and easy recipe! I put the wife's bard on the elevator with selos running, gave myself SoE, and then went back and forth to the forge - a good tip is to float over the wall outside the library and dive straight down to the forge building.
It costs something like 5pp per combine (using the Scent of Marr for celestial essence) which is phenominally cheap. Roughly 60 seconds per combine, not counting chatting, falling off elevator, getting stuck in trees and other things that exist in practice rather than theory!
The figures:
2-3 hours of tradeskilling (runing back and forth, making sub combines etc)
Less than 1kpp spent
7 smith dings (221-227).
I'm now going to farm the things needed for the next part of this quest to get me to 229 :).