I am not sure what you are looking for....there is not a hidden spacer in your headset. Your headset is a hiddenset integrated headset design, which means the bearing cups are integrated into the headtube of the frame.

If you need to replace your TTC (tall top cap -refering to the dustcap spacer) with a normal size one you may need to purchase new headset. Not know the exact specs of what you have, I can only guess at what would be a good replacement. I don't recall very many headsets on the market that look like what you have and most are campagnolo hiddenset clones/compatible...so this is my best guess for an affordable replacement with the normal/lower top dust cap:

New on Sale FSA Orbit CE Headset 1 1 8" Fits Campy Hiddenset Campagnolo | eBay

First thing you should do is ensure your fork is cut to the appropriate length. With the headset and stem installed there should be a 5mm gap from the top of the steerer tube to the top of the stem...much more of a gap than and your fork is considered too short; a gap less than 5mm may allow the top cap used to set the preload to bottom out against the top of the fork steerer tube when the bearing preload is set.

good luck

-j