Good question!
Under the current WPATH standards, Gender Dysphoria is applied to those who feel they are a gender *other than* the one they were assigned at birth--not the *opposite* gender.
One of the diagnostic codes used to process insurance claims for this is (as of Oct 1, 2015):
ICD-10-CM F64.1 Gender identity disorder in adolescence and adulthood
In contrast to the WPATH standards, the wording of this does indicate that "persistent desire for the physical characteristics and social roles that connote the opposite biological sex" is required.
That said, I know that non-binary trans folks are getting Top Surgery covered by insurance. I imagine the quality of the letter from your surgeon is a factor.
Here's a sample letter successfully used by Dr. Mosser.
Hope this helps!