There are 12 different Toyota sales regions in the USA and a few are even privately owned as in my Gulf States region.
Determining Your Region for Toyota Deals | U.S. News Best Cars
All regions don't have the same options as others and are determined by the Regional sales managers according to what they think/compute will sell in their region. Canada on the other hand has even fewer options and you basically get what they order from mother Toyota.
So bottom line is the Premium package for the SR5 is not available in your region unless you find a Sales manager to order one.That could take awhile as the ones coming off the assy lines are already allotted for other regions. Best to look in another region IMO if that's what you really want.