I would just use the 10% off on the Northridge site. It does work on Currie stuff but will not work on Evo suspension. Currie front lower arms after discount should be around $324.
as mentioned i would look on off road evo's site, northridge, or trail jeeps. all 3 will have the evo lower control arms. the discount from northridge should work for the control arms.
Northridge4x4 has fantastic cust service. If the currie arms are discounted, they use Johnny joints so thats a good way to go imho - but if you order from EVO you can get a sweet sticker too.
I personally have the currie front lower but the Evo I think are nicer because they are adjustable without having to remove the arm from one of the brackets.