Cyan is available in the Short Run Depot -
All the single-color stashes are there. The specific click is:
Just grab the pull-down menu and you'll see almost all the colors -
including Cyan - available. The only monochrome stash that is not
available is the Gray
The Grey's are a Dangling Carrot item because only Rabbits (with Rabbit points) can get it.
Cyan is no longer a "only Rabbits can get it" item - that's why it's on the Short Run index and not the Dangling Carrot index.
Also - remember if you're new to the pyramids, the way to get them now is via Treehouse sets. :)