Fuel Bricks
Magnoli the Hauler has Fuel Bricks for trade.  Can't find anything on the internet about them and can't find a CC icon for them either.
Keep in mind that you are playing MegaMod which has more than 100 mods in addition to Colonial Charter. Apparently one of the buildings added produces Fuel Bricks so that item gets added to the items you might be able to get from a Trading Post.