How many leaves are on yours, 4 or 5? There are both versions out there.
You could try Posies. They sell various versions, some have reversed eyes to drop the car lower, some have a higher arch to put it up more. If you shoot us some pictures of your front end in detail it will maybe show us what is going on. As Bonehead mentioned, it might have more to do with the mounting than the spring itself.
BTW, you can rearch your spring too, if you have a hydraulic press. We did this to the spring on my Son's '29. First of all we drew the profile of the main leaf on the garage floor for reference, then we drew lines on the spring every one inch. Next we put it in the press and put exactly the same number of pumps on the jack handle at each inch increment. (it only takes 2 or 3 pumps to really bend the spring, so be careful) Once we had it reshaped more arched we did the same to the other leaves. When it was bolted back together it sat a couple inches higher. A spring shop can do this for you too.
Don