The Hypercoil springs are going to run around $57 each.
7" vs 8":
7 inch hypercoil spring?
I ran 7's and it sat OK. But they don't do a 250# in a 7". If you go with an 8" spring, they will fit fine, you will get the performance that you're looking for, and there is many rates available, BUT you may not get the car to sit as low as you might want.