If you are using a 10 strand D97 string, normal .021 serving (BCY 62 or similar) with 2 extra strands layed down and served in with the string will fit most carbon nocks along with the Easton Uni-nock, .021 nylon will lay a bit flatter and may require a total of 3 strands. If you are wishing to use larger nocks, say glue on nocks (AAE, index, etc...) then the larger .030 would most likely be very close.
You shouldn't have to double serve a 10 strand at all, even if you have to use a few extra strands of serving instead of D97 or B50 material, you can build it up. Now it may look a little snakey the first time or two you try it, the trick is to get the jig tension set just right and to gently pull on the under laying strands as you serve over them and the main string. But, this is all depending on the type of nocks you are using and what type(s) of serving you have available. If I can be of any help, just let me know.