The "evolving tokens" ..i.e. I assume you mean "artifacts" are offered in the Spire, though in a very long rotation so it might take a few months to years to get the ones you need, especially if you don't do a lot in the game/spire. I believe they do show up in crafting from time to time as well. Probably going to be hard to get where your going playing less often since you are right that a lot of opportunities will slip by and not be seen.
AJ