The ones with the Tahoe motor are not available yet; GM does not have enough capacity to fulfill the demand for Tahoe and Yukon hybrids. There is only one plant that is producing these vehicles. At the moment, you can get it with 403hp motor only. The 332hp motor will become widely available after the summer, hopefully.
Since you brought up this issue, I wonder why anyone would pay such a hefty premium on essentially the same package as in Tahoe and Yukon with the same motor. I and a few others I know switched because of the motor.