Most of the Chinese crabbon fibber resellers will drill the rims with however many holes you want. Yoeleo would certainly knock you out some deep section carbon rims with a 36 hole count if you ask nicely. And with disc brakes, you don't have to worry about the brake track melting...
I'm having trouble working out which race you're entering where the difference between an Enve-SES and a Chinese knock-off is mission critical, but disc brakes and a dynohub are still the optimal solution.
Most of the Chinese crabbon fibber resellers will drill the rims with however many holes you want. Yoeleo would certainly knock you out some deep section carbon rims with a 36 hole count if you ask nicely. And with disc brakes, you don't have to worry about the brake track melting...