I have a CAAD10 with a really short steertube. Right now I have the setup pictured below, with a FSA OS-115 stem with 35mm stack.
I have a Ritchey C260 stem I would like to use (especially cause it'll match the seatpost) but it has a stack of 42m.

Right now the CaneCreek headset on it has 9mm stack. For the Ritchey to work, I'd have to lose at last 5mm in the headset. It is already pretty short, but what can I get shorter?

Can I get something like this?
SlamThatStem Headset Caps Let You, Uh, Slam That Stem

Would a woodman dust cap like this help?
WOOdman Components Road & x country freeride Mountain bikes

Any help is appreciated!