How to get sweet business.catalyst: wait until season of opulence and figure out how it drops then... It was only available through factions rallies a couple seasons back and is currently unavailable. Bungie has stated the 3 catalysts from faction rallies will become available in some fashion during season 7. Graviton Lance, sweet business, sunshot...but I'm more excited for these year 2 exotic catalysts coming.

Right now, you can’t. This was a faction rally earnable catalyst & rallies have been removed. Bungie said they are bringing the 3 faction rally catalysts back next season, but haven’t said what ways there will be to earn them.