We ordered cars every now and then at the Subie dealer I worked at. It was no big deal, but it takes FOREVER. Plan on 6-8 weeks.
We RARELY had to do it. Because whatever combination you want, its pretty easy to find a car close enough, and add the options you want. We would find a car, even if it was in the next state over, and get it shipped to us, then add on the options you wanted. 99% of the time we could do it for the same price if the customer stood their ground hard enough.
9 out of 10 customers, when faced with "leave $2000 CASH/CREDIT CARD, NON REFUNDABLE DEPOSIT for a car we can't promise when it will actually get here, but will likely be 6-8 weeks, possibly 10, but usually around 6" or "We can have another car here and make it exactly like the one you want, for $500 more, in 2-3 days" choice, 9 out of 10 will take the faster option. Of those 9 out of 10, 2-3 of them will hold their ground solid and still get the car for the same price as ordering it.
Then again, we were a pretty honest sales dept. I myself was dead honest, 100% of the time. And strangely enough, it worked. I explained how if they fight and fight for that extra $500, they could see it off the price of their car, but their interest would end up a little higher, or something, because at the end of the day it was a business and we couldn't give them a car for zero profit.