They came as part of the dealer kit here:
They are the same struts as the Version 7 STi type RA. They are for a sedan.
If you get these you have a lot of options: the "pink springs" from Myles/RaceComp Engineering, the older Ver7 pink springs, Prodrive springs, RS*R springs
Price is $350 shipped.. less than that if you're local.Here's what I ended up with:
-STi V7 struts
The springs are just the regular blue Prodrives, but the struts are wagon specific. BTW, I opted for the Prodrive springs cause I wanted a shade more drop than the STi V7 springs offered and they address your concern #4. From my research, the Prodrive and STi V7 spring have just about the same spring rate.
Didn't even bother with camber plates or bolts. If anything, I might add the Group N strut mounts someday.
I track my car 3-4 time a year and drive pretty aggressively. This combo has worked out very well. Honestly, the struts could be a pinch more stiff at the track. But, it not enough for me to justify adjustable struts (Koni inserts or KYBs).