if you do need something custom you can try here
http://www.allsprings.20m.com/ Talk to Aldo, take your original springs in, with your static height and droop height measurements he will check the spring rate, tell him how much higher you want the car and what spring rate you want he will custom make you a set. it may take a couple of go's in and out to fine tune, but for the price they charge they are bloody good. I am happy with my springs from them.