Who have you talked to? My 2002 IS300 originally came from Metro, but I got it used from Classic in Mentor. I think maybe the general manager would be more inclined to know what they can order and maybe more willing than a salesman.
I got the first IS350 in the Huntsivlle, AL area. At that time the only options being shipped in this region was the 18" wheels and preferred opton group. Now the list of options includes more. Each region seems to have it's own distinct list of available options. Lexus doesn't build to order, but the dealer ought to be able to get dibs on a car like you want, and get it whenever it is built. From what I've read, the ML system was very scarce in the beginning, but should become more available after January.
Hope this helps.