Yes, the headset stack (and any spacers) must be included. So if you have a 202mm steerer, and a combined stem/HT of 180mm, you have to find a HS with a stack of about 20-21mm and you will not be able to use any spacers in that case. For reference I believe a Chris King HS has a stack of about 28mm. I am assuming your bike uses a conventional (non-integrated) headset.
I would find another fork if it were me. The one you are looking at is right on the edge and gives you little if any fitting flexibility.
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