On your list, the bottom 3 are probably the best options (though it sounds like K-Sports are a good option) for serious Autocross use. I have the AWR/Bilstein combo on my FSP car, and its great. For tuning the suspension and handling I adjust the rear swaybar (AWR 21.5mm). You can get an adjustable front bar, but I think stock front bar is really all you need. Plus with all the alignment/ride height adjustments you can make, you don't really need the adjustable shocks to adjust the handling. Sure, ultimately they would be nice to have, but a correctly valved set of Bilsteins are not a bad compromise.
Springs: Both Justin and I are running 450# front, 600# rear and it really works well. Its not the nicest ride for Daily Driving, but its great on the autocross. I had an event this past weekend with some rolling bumps in the lot and it really never felt unsettled at speed.
I also strongly recommend front camber plates. It makes the front tires work more evenly accross the tread- adjust your pressures to get the best contact patch. The difference in grip is amazing when you are actually using the whole tire instead of just the outer half!
I have to recommend not buying anything at all if you can't afford the good stuff. If you are serious about building a competitve autocross car- wait until you can afford the real parts- because you are just going to buy them eventually.
If you are going to buy things piece by piece...maybe get just the rear shocks and coilovers, but at a lower valving and spring rate (450#). Then have everything revalved when you go for the front suspension- put the 450's on the front, and get some 600's for the rear.